Develop Reference

How to get Mobile number from SIM card in Android Programmatically using kotlin language?

I tried using below piece of code but it is not giving me the number. Your information would be great help.
Code below:
val subscription =SubscriptionManager.from(context).activeSubscriptionInfoList
for (subscriptionInfo in subscription)
{
val number = subscriptionInfo.number
Log.e("Test", " Number is " + number)
}

Correct way to get IMEI Number KOTLIN
try{
val tm = getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
val IMEI = tm.getImei()
if (IMEI != null)
Toast.makeText(this, "IMEI number: " + IMEI,
Toast.LENGTH_LONG).show()
}catch (ex:Exception){
Log.e("",ex.message)
}
Including asking for Permission
if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this, android.Manifest.permission.READ_PHONE_STATE)) {
} else { ActivityCompat.requestPermissions(this, arrayOf(android.Manifest.permission.READ_PHONE_STATE), 2) } }
Don't forget AndroidManifest.xml
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>

Taken from this answer and translated to kotlin:
Getting the Phone Number, IMEI, and SIM Card ID
val tm = getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
// For SIM card, use the getSimSerialNumber()
//---get the SIM card ID---
val simID = tm.simSerialNumber
if (simID != null)
Toast.makeText(this, "SIM card ID: " + simID,
Toast.LENGTH_LONG).show()
Phone number of your phone, use the getLine1Number() (some device's dont return the phone number)
//---get the phone number---
val telNumber = tm.line1Number
if (telNumber != null)
Toast.makeText(this, "Phone number: " + telNumber,
Toast.LENGTH_LONG).show()
// IMEI number of the phone, use the getDeviceId()
//---get the IMEI number---
val IMEI = tm.deviceId
if (IMEI != null)
Toast.makeText(this, "IMEI number: " + IMEI,
Toast.LENGTH_LONG).show()
Permissions needed:
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
Please note that some devices could not return the phone number due to its internal implementation.

Right now you can not access these Info according to docs:
getSerial()
getImei()
getDeviceId()
getMeid()
getSimSerialNumber()
getSubscriberId()
If your app targets Android 10 or higher, a SecurityException occurs.
If your app targets Android 9 (API level 28) or lower, the method returns null or placeholder data if the app has the READ_PHONE_STATE permission. Otherwise, a SecurityException occurs.

Unable to get own mobile number [duplicate]

How can I programmatically get the phone number of the device that is running my android app?

Code:
TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();
Required Permission:
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
Caveats:
According to the highly upvoted comments, there are a few caveats to be aware of. This can return null or "" or even "???????", and it can return a stale phone number that is no longer valid. If you want something that uniquely identifies the device, you should use getDeviceId() instead.

There is no guaranteed solution to this problem because the phone number is not physically stored on all SIM-cards, or broadcasted from the network to the phone. This is especially true in some countries which requires physical address verification, with number assignment only happening afterwards. Phone number assignment happens on the network - and can be changed without changing the SIM card or device (e.g. this is how porting is supported).
I know it is pain, but most likely the best solution is just to ask the user to enter his/her phone number once and store it.

Update: This answer is no longer available as Whatsapp had stopped exposing the phone number as account name, kindly disregard this answer.
There is actually an alternative solution you might want to consider, if you can't get it through telephony service.
As of today, you can rely on another big application Whatsapp, using AccountManager. Millions of devices have this application installed and if you can't get the phone number via TelephonyManager, you may give this a shot.
Permission:
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
Code:
AccountManager am = AccountManager.get(this);
Account[] accounts = am.getAccounts();
for (Account ac : accounts) {
String acname = ac.name;
String actype = ac.type;
// Take your time to look at all available accounts
System.out.println("Accounts : " + acname + ", " + actype);
}
Check actype for WhatsApp account
if(actype.equals("com.whatsapp")){
String phoneNumber = ac.name;
}
Of course you may not get it if user did not install WhatsApp, but its worth to try anyway.
And remember you should always ask user for confirmation.

So that's how you request a phone number through the Play Services API without the permission and hacks. Source and Full example.
In your build.gradle (version 10.2.x and higher required):
compile "com.google.android.gms:play-services-auth:$gms_version"
In your activity (the code is simplified):
#Override
protected void onCreate(Bundle savedInstanceState) {
// ...
googleApiClient = new GoogleApiClient.Builder(this)
.addApi(Auth.CREDENTIALS_API)
.build();
requestPhoneNumber(result -> {
phoneET.setText(result);
});
}
public void requestPhoneNumber(SimpleCallback<String> callback) {
phoneNumberCallback = callback;
HintRequest hintRequest = new HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build();
PendingIntent intent = Auth.CredentialsApi.getHintPickerIntent(googleApiClient, hintRequest);
try {
startIntentSenderForResult(intent.getIntentSender(), PHONE_NUMBER_RC, null, 0, 0, 0);
} catch (IntentSender.SendIntentException e) {
Logs.e(TAG, "Could not start hint picker Intent", e);
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PHONE_NUMBER_RC) {
if (resultCode == RESULT_OK) {
Credential cred = data.getParcelableExtra(Credential.EXTRA_KEY);
if (phoneNumberCallback != null){
phoneNumberCallback.onSuccess(cred.getId());
}
}
phoneNumberCallback = null;
}
}
This will generate a dialog like this:

As posted in my earlier answer
Use below code :
TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();
In AndroidManifest.xml, give the following permission:
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
But remember, this code does not always work, since Cell phone number is dependent on the SIM Card and the Network operator / Cell phone carrier.
Also, try checking in Phone--> Settings --> About --> Phone Identity, If you are able to view the Number there, the probability of getting the phone number from above code is higher. If you are not able to view the phone number in the settings, then you won't be able to get via this code!
Suggested Workaround:
Get the user's phone number as manual input from the user.
Send a code to the user's mobile number via SMS.
Ask user to enter the code to confirm the phone number.
Save the number in sharedpreference.
Do the above 4 steps as one time activity during the app's first launch. Later on, whenever phone number is required, use the value available in shared preference.

There is a new Android api that allows the user to select their phonenumber without the need for a permission. Take a look at:
https://android-developers.googleblog.com/2017/10/effective-phone-number-verification.html
// Construct a request for phone numbers and show the picker
private void requestHint() {
HintRequest hintRequest = new HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build();
PendingIntent intent = Auth.CredentialsApi.getHintPickerIntent(
apiClient, hintRequest);
startIntentSenderForResult(intent.getIntentSender(),
RESOLVE_HINT, null, 0, 0, 0);
}

private String getMyPhoneNumber(){
TelephonyManager mTelephonyMgr;
mTelephonyMgr = (TelephonyManager)
getSystemService(Context.TELEPHONY_SERVICE);
return mTelephonyMgr.getLine1Number();
}
private String getMy10DigitPhoneNumber(){
String s = getMyPhoneNumber();
return s != null && s.length() > 2 ? s.substring(2) : null;
}
Code taken from http://www.androidsnippets.com/get-my-phone-number

Just want to add a bit here to above explanations in the above answers. Which will save time for others as well.
In my case this method didn't returned any mobile number, an empty string was returned. It was due to the case that I had ported my number on the new sim. So if I go into the Settings>About Phone>Status>My Phone Number it shows me "Unknown".

Sometimes, below code returns null or blank string.
TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();
With below permission
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
There is another way you will be able to get your phone number, I haven't tested this on multiple devices but above code is not working every time.
Try below code:
String main_data[] = {"data1", "is_primary", "data3", "data2", "data1", "is_primary", "photo_uri", "mimetype"};
Object object = getContentResolver().query(Uri.withAppendedPath(android.provider.ContactsContract.Profile.CONTENT_URI, "data"),
main_data, "mimetype=?",
new String[]{"vnd.android.cursor.item/phone_v2"},
"is_primary DESC");
if (object != null) {
do {
if (!((Cursor) (object)).moveToNext())
break;
// This is the phoneNumber
String s1 = ((Cursor) (object)).getString(4);
} while (true);
((Cursor) (object)).close();
}
You will need to add these two permissions.
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.READ_PROFILE" />
Hope this helps,
Thanks!

First of all getting users mobile number is against the Ethical policy, earlier it was possible but now as per my research there no solid solution available for this, By using some code it is possible to get mobile number but no guarantee may be it will work only in few device. After lot of research i found only three solution but they are not working in all device.
There is the following reason why we are not getting.
1.Android device and new Sim Card not storing mobile number if mobile number is not available in device and in sim then how it is possible to get number, if any old sim card having mobile number then using Telephony manager we can get the number other wise it will return the “null” or “” or “??????”
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
TelephonyManager tel= (TelephonyManager)this.getSystemService(Context.
TELEPHONY_SERVICE);
String PhoneNumber = tel.getLine1Number();
Note:- I have tested this solution in following device Moto x, Samsung Tab 4, Samsung S4, Nexus 5 and Redmi 2 prime but it doesn’t work every
time it return empty string so conclusion is it's useless
This method is working only in Redmi 2 prime, but for this need to add
read contact permission in manifest.
Note:- This is also not the guaranteed and efficient solution, I have tested this solution in many device but it worked only in Redmi 2 prime
which is dual sim device it gives me two mobile number first one is
correct but the second one is not belong to my second sim it belong to
my some old sim card which i am not using.
String main_data[] = {"data1", "is_primary", "data3", "data2", "data1",
"is_primary", "photo_uri", "mimetype"};
Object object = getContentResolver().
query(Uri.withAppendedPath(android.provider.ContactsContract.Profile.CONTENT_URI, "data"),
main_data, "mimetype=?",
new String[]{"vnd.android.cursor.item/phone_v2"},
"is_primary DESC");
String s1="";
if (object != null) {
do {
if (!((Cursor) (object)).moveToNext())
break;
// This is the phoneNumber
s1 =s1+"---"+ ((Cursor) (object)).getString(4);
} while (true);
((Cursor) (object)).close();
}
In my research i have found earlier it was possible to get mobile number using WhatsApp account but now new Whatsapp version doesn’t storing user's mobile number.
Conclusion:- Android doesn’t have any guaranteed solution to get
user's mobile number programmatically.
Suggestion:- 1. If you want to verify user’s mobile number then ask to
user to provide his number, using otp you can can verify that.
If you want to identify the user’s device, for this you can easily get device IMEI number.

TelephonyManager is not the right solution, because in some cases the number is not stored in the SIM. I suggest that you should use the shared preference to store the user's phone number for the first time the application is open and the number will used whenever you need.

This is a more simplified answer:
public String getMyPhoneNumber()
{
return ((TelephonyManager) getSystemService(TELEPHONY_SERVICE))
.getLine1Number();
}

Here's a combination of the solutions I've found (sample project here, if you want to also check auto-fill):
manifest
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
build.gradle
implementation "com.google.android.gms:play-services-auth:17.0.0"
MainActivity.kt
class MainActivity : AppCompatActivity() {
private lateinit var googleApiClient: GoogleApiClient
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
tryGetCurrentUserPhoneNumber(this)
googleApiClient = GoogleApiClient.Builder(this).addApi(Auth.CREDENTIALS_API).build()
if (phoneNumber.isEmpty()) {
val hintRequest = HintRequest.Builder().setPhoneNumberIdentifierSupported(true).build()
val intent = Auth.CredentialsApi.getHintPickerIntent(googleApiClient, hintRequest)
try {
startIntentSenderForResult(intent.intentSender, REQUEST_PHONE_NUMBER, null, 0, 0, 0);
} catch (e: IntentSender.SendIntentException) {
Toast.makeText(this, "failed to show phone picker", Toast.LENGTH_SHORT).show()
}
} else
onGotPhoneNumberToSendTo()
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == REQUEST_PHONE_NUMBER) {
if (resultCode == Activity.RESULT_OK) {
val cred: Credential? = data?.getParcelableExtra(Credential.EXTRA_KEY)
phoneNumber = cred?.id ?: ""
if (phoneNumber.isEmpty())
Toast.makeText(this, "failed to get phone number", Toast.LENGTH_SHORT).show()
else
onGotPhoneNumberToSendTo()
}
}
}
private fun onGotPhoneNumberToSendTo() {
Toast.makeText(this, "got number:$phoneNumber", Toast.LENGTH_SHORT).show()
}
companion object {
private const val REQUEST_PHONE_NUMBER = 1
private var phoneNumber = ""
#SuppressLint("MissingPermission", "HardwareIds")
private fun tryGetCurrentUserPhoneNumber(context: Context): String {
if (phoneNumber.isNotEmpty())
return phoneNumber
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
val subscriptionManager = context.getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE) as SubscriptionManager
try {
subscriptionManager.activeSubscriptionInfoList?.forEach {
val number: String? = it.number
if (!number.isNullOrBlank()) {
phoneNumber = number
return number
}
}
} catch (ignored: Exception) {
}
}
try {
val telephonyManager = context.getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
val number = telephonyManager.line1Number ?: ""
if (!number.isBlank()) {
phoneNumber = number
return number
}
} catch (e: Exception) {
}
return ""
}
}
}

Add this dependency:
implementation 'com.google.android.gms:play-services-auth:18.0.0'
To fetch phone number list use this:
val hintRequest = HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build()
val intent = Credentials.getClient(context).getHintPickerIntent(hintRequest)
startIntentSenderForResult(
intent.intentSender,
PHONE_NUMBER_FETCH_REQUEST_CODE,
null,
0,
0,
0,
null
)
After tap on play services dialog:
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent? {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == PHONE_NUMBER_FETCH_REQUEST_CODE) {
data?.getParcelableExtra<Credential>(Credential.EXTRA_KEY)?.id?.let {
useFetchedPhoneNumber(it)
}
}
}

A little contribution. In my case, the code launched an error exception. I have needed put an annotation that for the code be run and fix that problem. Here I let this code.
public static String getLineNumberPhone(Context scenario) {
TelephonyManager tMgr = (TelephonyManager) scenario.getSystemService(Context.TELEPHONY_SERVICE);
#SuppressLint("MissingPermission") String mPhoneNumber = tMgr.getLine1Number();
return mPhoneNumber;
}

For android version >= LOLLIPOP_MR1 :
Add permission :
And call this :
val subscriptionManager =
getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE) as SubscriptionManager
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) == PackageManager.PERMISSION_GRANTED) {
val list = subscriptionManager.activeSubscriptionInfoList
for (info in list) {
Log.d(TAG, "number " + info.number)
Log.d(TAG, "network name : " + info.carrierName)
Log.d(TAG, "country iso " + info.countryIso)
}
}

I noticed several answers posting the same thing. First of all things changed as per 2021, onActivityResult is deprecated. Here is the non-deprecated solution.
private fun requestHint() {
val hintRequest = HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build()
val intent = Credentials.getClient(this).getHintPickerIntent(hintRequest)
val intentSender = IntentSenderRequest.Builder(intent.intentSender).build()
val resultLauncher = registerForActivityResult(
ActivityResultContracts.StartIntentSenderForResult()
) { result ->
if (result.resultCode == Activity.RESULT_OK) {
val credential: Credential? = result.data?.getParcelableExtra(Credential.EXTRA_KEY)
// Phone number with country code
Log.i("mTag", "Selected phone No: ${credential?.id}")
}
}
resultLauncher.launch(intentSender)
}
Note: While many of you think this allows you to retrieve user's mobile phone number. That is usually not the case. Google Play Services has cached few phone numbers and sometimes the dialog shows phone numbers in which none belongs to user.
An important import com.google.android.gms.auth.api.credentials.Credential
Reference Documentation provides details but the code is somewhat deprecated.

Although it's possible to have multiple voicemail accounts, when calling from your own number, carriers route you to voicemail. So, TelephonyManager.getVoiceMailNumber() or TelephonyManager.getCompleteVoiceMailNumber(), depending on the flavor you need.
Hope this helps.

Wouldn't be recommending to use TelephonyManager as it requires the app to require READ_PHONE_STATE permission during runtime.
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
Should be using Google's Play Service for Authentication, and it will able to allow User to select which phoneNumber to use, and handles multiple SIM cards, rather than us trying to guess which one is the primary SIM Card.
implementation "com.google.android.gms:play-services-auth:$play_service_auth_version"
fun main() {
val googleApiClient = GoogleApiClient.Builder(context)
.addApi(Auth.CREDENTIALS_API).build()
val hintRequest = HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build()
val hintPickerIntent = Auth.CredentialsApi.getHintPickerIntent(
googleApiClient, hintRequest
)
startIntentSenderForResult(
hintPickerIntent.intentSender, REQUEST_PHONE_NUMBER, null, 0, 0, 0
)
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
when (requestCode) {
REQUEST_PHONE_NUMBER -> {
if (requestCode == Activity.RESULT_OK) {
val credential = data?.getParcelableExtra<Credential>(Credential.EXTRA_KEY)
val selectedPhoneNumber = credential?.id
}
}
}
}

If I'm getting number from voiceMailNumer then it is working good -
val telephonyManager = getSystemService(TELEPHONY_SERVICE) as TelephonyManager
if (ActivityCompat.checkSelfPermission(this,
Manifest.permission.READ_PHONE_STATE) == PackageManager.PERMISSION_GRANTED
) {
Log.d("number", telephonyManager.voiceMailNumber.toString())
}

Firstly Initalize your sign in Intent like this
private val signInIntent = registerForActivityResult(ActivityResultContracts.StartIntentSenderForResult()) { result ->
try {
val phoneNumber = Identity.getSignInClient(requireContext()).getPhoneNumberFromIntent(result.data)
// Note phone number will be in country code + phone number format
} catch (e: Exception) {
}
}
To open google play intent and show phone number associated with google account use this
val phoneNumberHintIntentRequest = GetPhoneNumberHintIntentRequest.builder()
.build()
Identity.getSignInClient(requireContext())
.getPhoneNumberHintIntent(phoneNumberHintIntentRequest)
.addOnSuccessListener { pendingIntent ->
signInIntent.launch(IntentSenderRequest.Builder(pendingIntent).build())
}.addOnFailureListener {
it.printStackTrace()
}
Note:
This will fail if user is disabled phone number sharing. If is it so user have to enable that from Settings -> Google -> Auto-fill -> Phone Number sharing
This will not working if you are using emulated device where play services is not available

while working on a security app which needed to get the phone number of who so ever my phone might get into their hands, I had to do this;
1. receive Boot completed and then try getting Line1_Number from telephonyManager which returns a string result.
2. compare the String result with my own phone number and if they don't match or string returns null then,
3. secretly send an SMS containing the string result plus a special sign to my office number.
4. if message sending fails, start a service and keep trying after each hour until sent SMS pending intent returns successful.
With this steps I could get the number of the person using my lost phone.
it doesn't matter if the person is charged.

how to get mobile number from my current Phone? it's display blank Mobile Number in Log. but when run on emulator its display emulator Number [duplicate]

How can I programmatically get the phone number of the device that is running my android app?

Code:
TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();
Required Permission:
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
Caveats:
According to the highly upvoted comments, there are a few caveats to be aware of. This can return null or "" or even "???????", and it can return a stale phone number that is no longer valid. If you want something that uniquely identifies the device, you should use getDeviceId() instead.

There is no guaranteed solution to this problem because the phone number is not physically stored on all SIM-cards, or broadcasted from the network to the phone. This is especially true in some countries which requires physical address verification, with number assignment only happening afterwards. Phone number assignment happens on the network - and can be changed without changing the SIM card or device (e.g. this is how porting is supported).
I know it is pain, but most likely the best solution is just to ask the user to enter his/her phone number once and store it.

Update: This answer is no longer available as Whatsapp had stopped exposing the phone number as account name, kindly disregard this answer.
There is actually an alternative solution you might want to consider, if you can't get it through telephony service.
As of today, you can rely on another big application Whatsapp, using AccountManager. Millions of devices have this application installed and if you can't get the phone number via TelephonyManager, you may give this a shot.
Permission:
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
Code:
AccountManager am = AccountManager.get(this);
Account[] accounts = am.getAccounts();
for (Account ac : accounts) {
String acname = ac.name;
String actype = ac.type;
// Take your time to look at all available accounts
System.out.println("Accounts : " + acname + ", " + actype);
}
Check actype for WhatsApp account
if(actype.equals("com.whatsapp")){
String phoneNumber = ac.name;
}
Of course you may not get it if user did not install WhatsApp, but its worth to try anyway.
And remember you should always ask user for confirmation.

So that's how you request a phone number through the Play Services API without the permission and hacks. Source and Full example.
In your build.gradle (version 10.2.x and higher required):
compile "com.google.android.gms:play-services-auth:$gms_version"
In your activity (the code is simplified):
#Override
protected void onCreate(Bundle savedInstanceState) {
// ...
googleApiClient = new GoogleApiClient.Builder(this)
.addApi(Auth.CREDENTIALS_API)
.build();
requestPhoneNumber(result -> {
phoneET.setText(result);
});
}
public void requestPhoneNumber(SimpleCallback<String> callback) {
phoneNumberCallback = callback;
HintRequest hintRequest = new HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build();
PendingIntent intent = Auth.CredentialsApi.getHintPickerIntent(googleApiClient, hintRequest);
try {
startIntentSenderForResult(intent.getIntentSender(), PHONE_NUMBER_RC, null, 0, 0, 0);
} catch (IntentSender.SendIntentException e) {
Logs.e(TAG, "Could not start hint picker Intent", e);
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PHONE_NUMBER_RC) {
if (resultCode == RESULT_OK) {
Credential cred = data.getParcelableExtra(Credential.EXTRA_KEY);
if (phoneNumberCallback != null){
phoneNumberCallback.onSuccess(cred.getId());
}
}
phoneNumberCallback = null;
}
}
This will generate a dialog like this:

As posted in my earlier answer
Use below code :
TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();
In AndroidManifest.xml, give the following permission:
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
But remember, this code does not always work, since Cell phone number is dependent on the SIM Card and the Network operator / Cell phone carrier.
Also, try checking in Phone--> Settings --> About --> Phone Identity, If you are able to view the Number there, the probability of getting the phone number from above code is higher. If you are not able to view the phone number in the settings, then you won't be able to get via this code!
Suggested Workaround:
Get the user's phone number as manual input from the user.
Send a code to the user's mobile number via SMS.
Ask user to enter the code to confirm the phone number.
Save the number in sharedpreference.
Do the above 4 steps as one time activity during the app's first launch. Later on, whenever phone number is required, use the value available in shared preference.

There is a new Android api that allows the user to select their phonenumber without the need for a permission. Take a look at:
https://android-developers.googleblog.com/2017/10/effective-phone-number-verification.html
// Construct a request for phone numbers and show the picker
private void requestHint() {
HintRequest hintRequest = new HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build();
PendingIntent intent = Auth.CredentialsApi.getHintPickerIntent(
apiClient, hintRequest);
startIntentSenderForResult(intent.getIntentSender(),
RESOLVE_HINT, null, 0, 0, 0);
}

private String getMyPhoneNumber(){
TelephonyManager mTelephonyMgr;
mTelephonyMgr = (TelephonyManager)
getSystemService(Context.TELEPHONY_SERVICE);
return mTelephonyMgr.getLine1Number();
}
private String getMy10DigitPhoneNumber(){
String s = getMyPhoneNumber();
return s != null && s.length() > 2 ? s.substring(2) : null;
}
Code taken from http://www.androidsnippets.com/get-my-phone-number

Just want to add a bit here to above explanations in the above answers. Which will save time for others as well.
In my case this method didn't returned any mobile number, an empty string was returned. It was due to the case that I had ported my number on the new sim. So if I go into the Settings>About Phone>Status>My Phone Number it shows me "Unknown".

Sometimes, below code returns null or blank string.
TelephonyManager tMgr = (TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
String mPhoneNumber = tMgr.getLine1Number();
With below permission
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
There is another way you will be able to get your phone number, I haven't tested this on multiple devices but above code is not working every time.
Try below code:
String main_data[] = {"data1", "is_primary", "data3", "data2", "data1", "is_primary", "photo_uri", "mimetype"};
Object object = getContentResolver().query(Uri.withAppendedPath(android.provider.ContactsContract.Profile.CONTENT_URI, "data"),
main_data, "mimetype=?",
new String[]{"vnd.android.cursor.item/phone_v2"},
"is_primary DESC");
if (object != null) {
do {
if (!((Cursor) (object)).moveToNext())
break;
// This is the phoneNumber
String s1 = ((Cursor) (object)).getString(4);
} while (true);
((Cursor) (object)).close();
}
You will need to add these two permissions.
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.READ_PROFILE" />
Hope this helps,
Thanks!

First of all getting users mobile number is against the Ethical policy, earlier it was possible but now as per my research there no solid solution available for this, By using some code it is possible to get mobile number but no guarantee may be it will work only in few device. After lot of research i found only three solution but they are not working in all device.
There is the following reason why we are not getting.
1.Android device and new Sim Card not storing mobile number if mobile number is not available in device and in sim then how it is possible to get number, if any old sim card having mobile number then using Telephony manager we can get the number other wise it will return the “null” or “” or “??????”
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
TelephonyManager tel= (TelephonyManager)this.getSystemService(Context.
TELEPHONY_SERVICE);
String PhoneNumber = tel.getLine1Number();
Note:- I have tested this solution in following device Moto x, Samsung Tab 4, Samsung S4, Nexus 5 and Redmi 2 prime but it doesn’t work every
time it return empty string so conclusion is it's useless
This method is working only in Redmi 2 prime, but for this need to add
read contact permission in manifest.
Note:- This is also not the guaranteed and efficient solution, I have tested this solution in many device but it worked only in Redmi 2 prime
which is dual sim device it gives me two mobile number first one is
correct but the second one is not belong to my second sim it belong to
my some old sim card which i am not using.
String main_data[] = {"data1", "is_primary", "data3", "data2", "data1",
"is_primary", "photo_uri", "mimetype"};
Object object = getContentResolver().
query(Uri.withAppendedPath(android.provider.ContactsContract.Profile.CONTENT_URI, "data"),
main_data, "mimetype=?",
new String[]{"vnd.android.cursor.item/phone_v2"},
"is_primary DESC");
String s1="";
if (object != null) {
do {
if (!((Cursor) (object)).moveToNext())
break;
// This is the phoneNumber
s1 =s1+"---"+ ((Cursor) (object)).getString(4);
} while (true);
((Cursor) (object)).close();
}
In my research i have found earlier it was possible to get mobile number using WhatsApp account but now new Whatsapp version doesn’t storing user's mobile number.
Conclusion:- Android doesn’t have any guaranteed solution to get
user's mobile number programmatically.
Suggestion:- 1. If you want to verify user’s mobile number then ask to
user to provide his number, using otp you can can verify that.
If you want to identify the user’s device, for this you can easily get device IMEI number.

TelephonyManager is not the right solution, because in some cases the number is not stored in the SIM. I suggest that you should use the shared preference to store the user's phone number for the first time the application is open and the number will used whenever you need.

This is a more simplified answer:
public String getMyPhoneNumber()
{
return ((TelephonyManager) getSystemService(TELEPHONY_SERVICE))
.getLine1Number();
}

Here's a combination of the solutions I've found (sample project here, if you want to also check auto-fill):
manifest
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
build.gradle
implementation "com.google.android.gms:play-services-auth:17.0.0"
MainActivity.kt
class MainActivity : AppCompatActivity() {
private lateinit var googleApiClient: GoogleApiClient
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
tryGetCurrentUserPhoneNumber(this)
googleApiClient = GoogleApiClient.Builder(this).addApi(Auth.CREDENTIALS_API).build()
if (phoneNumber.isEmpty()) {
val hintRequest = HintRequest.Builder().setPhoneNumberIdentifierSupported(true).build()
val intent = Auth.CredentialsApi.getHintPickerIntent(googleApiClient, hintRequest)
try {
startIntentSenderForResult(intent.intentSender, REQUEST_PHONE_NUMBER, null, 0, 0, 0);
} catch (e: IntentSender.SendIntentException) {
Toast.makeText(this, "failed to show phone picker", Toast.LENGTH_SHORT).show()
}
} else
onGotPhoneNumberToSendTo()
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == REQUEST_PHONE_NUMBER) {
if (resultCode == Activity.RESULT_OK) {
val cred: Credential? = data?.getParcelableExtra(Credential.EXTRA_KEY)
phoneNumber = cred?.id ?: ""
if (phoneNumber.isEmpty())
Toast.makeText(this, "failed to get phone number", Toast.LENGTH_SHORT).show()
else
onGotPhoneNumberToSendTo()
}
}
}
private fun onGotPhoneNumberToSendTo() {
Toast.makeText(this, "got number:$phoneNumber", Toast.LENGTH_SHORT).show()
}
companion object {
private const val REQUEST_PHONE_NUMBER = 1
private var phoneNumber = ""
#SuppressLint("MissingPermission", "HardwareIds")
private fun tryGetCurrentUserPhoneNumber(context: Context): String {
if (phoneNumber.isNotEmpty())
return phoneNumber
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
val subscriptionManager = context.getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE) as SubscriptionManager
try {
subscriptionManager.activeSubscriptionInfoList?.forEach {
val number: String? = it.number
if (!number.isNullOrBlank()) {
phoneNumber = number
return number
}
}
} catch (ignored: Exception) {
}
}
try {
val telephonyManager = context.getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
val number = telephonyManager.line1Number ?: ""
if (!number.isBlank()) {
phoneNumber = number
return number
}
} catch (e: Exception) {
}
return ""
}
}
}

Add this dependency:
implementation 'com.google.android.gms:play-services-auth:18.0.0'
To fetch phone number list use this:
val hintRequest = HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build()
val intent = Credentials.getClient(context).getHintPickerIntent(hintRequest)
startIntentSenderForResult(
intent.intentSender,
PHONE_NUMBER_FETCH_REQUEST_CODE,
null,
0,
0,
0,
null
)
After tap on play services dialog:
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent? {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == PHONE_NUMBER_FETCH_REQUEST_CODE) {
data?.getParcelableExtra<Credential>(Credential.EXTRA_KEY)?.id?.let {
useFetchedPhoneNumber(it)
}
}
}

A little contribution. In my case, the code launched an error exception. I have needed put an annotation that for the code be run and fix that problem. Here I let this code.
public static String getLineNumberPhone(Context scenario) {
TelephonyManager tMgr = (TelephonyManager) scenario.getSystemService(Context.TELEPHONY_SERVICE);
#SuppressLint("MissingPermission") String mPhoneNumber = tMgr.getLine1Number();
return mPhoneNumber;
}

For android version >= LOLLIPOP_MR1 :
Add permission :
And call this :
val subscriptionManager =
getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE) as SubscriptionManager
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) == PackageManager.PERMISSION_GRANTED) {
val list = subscriptionManager.activeSubscriptionInfoList
for (info in list) {
Log.d(TAG, "number " + info.number)
Log.d(TAG, "network name : " + info.carrierName)
Log.d(TAG, "country iso " + info.countryIso)
}
}

I noticed several answers posting the same thing. First of all things changed as per 2021, onActivityResult is deprecated. Here is the non-deprecated solution.
private fun requestHint() {
val hintRequest = HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build()
val intent = Credentials.getClient(this).getHintPickerIntent(hintRequest)
val intentSender = IntentSenderRequest.Builder(intent.intentSender).build()
val resultLauncher = registerForActivityResult(
ActivityResultContracts.StartIntentSenderForResult()
) { result ->
if (result.resultCode == Activity.RESULT_OK) {
val credential: Credential? = result.data?.getParcelableExtra(Credential.EXTRA_KEY)
// Phone number with country code
Log.i("mTag", "Selected phone No: ${credential?.id}")
}
}
resultLauncher.launch(intentSender)
}
Note: While many of you think this allows you to retrieve user's mobile phone number. That is usually not the case. Google Play Services has cached few phone numbers and sometimes the dialog shows phone numbers in which none belongs to user.
An important import com.google.android.gms.auth.api.credentials.Credential
Reference Documentation provides details but the code is somewhat deprecated.

Although it's possible to have multiple voicemail accounts, when calling from your own number, carriers route you to voicemail. So, TelephonyManager.getVoiceMailNumber() or TelephonyManager.getCompleteVoiceMailNumber(), depending on the flavor you need.
Hope this helps.

Wouldn't be recommending to use TelephonyManager as it requires the app to require READ_PHONE_STATE permission during runtime.
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
Should be using Google's Play Service for Authentication, and it will able to allow User to select which phoneNumber to use, and handles multiple SIM cards, rather than us trying to guess which one is the primary SIM Card.
implementation "com.google.android.gms:play-services-auth:$play_service_auth_version"
fun main() {
val googleApiClient = GoogleApiClient.Builder(context)
.addApi(Auth.CREDENTIALS_API).build()
val hintRequest = HintRequest.Builder()
.setPhoneNumberIdentifierSupported(true)
.build()
val hintPickerIntent = Auth.CredentialsApi.getHintPickerIntent(
googleApiClient, hintRequest
)
startIntentSenderForResult(
hintPickerIntent.intentSender, REQUEST_PHONE_NUMBER, null, 0, 0, 0
)
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
when (requestCode) {
REQUEST_PHONE_NUMBER -> {
if (requestCode == Activity.RESULT_OK) {
val credential = data?.getParcelableExtra<Credential>(Credential.EXTRA_KEY)
val selectedPhoneNumber = credential?.id
}
}
}
}

If I'm getting number from voiceMailNumer then it is working good -
val telephonyManager = getSystemService(TELEPHONY_SERVICE) as TelephonyManager
if (ActivityCompat.checkSelfPermission(this,
Manifest.permission.READ_PHONE_STATE) == PackageManager.PERMISSION_GRANTED
) {
Log.d("number", telephonyManager.voiceMailNumber.toString())
}

Firstly Initalize your sign in Intent like this
private val signInIntent = registerForActivityResult(ActivityResultContracts.StartIntentSenderForResult()) { result ->
try {
val phoneNumber = Identity.getSignInClient(requireContext()).getPhoneNumberFromIntent(result.data)
// Note phone number will be in country code + phone number format
} catch (e: Exception) {
}
}
To open google play intent and show phone number associated with google account use this
val phoneNumberHintIntentRequest = GetPhoneNumberHintIntentRequest.builder()
.build()
Identity.getSignInClient(requireContext())
.getPhoneNumberHintIntent(phoneNumberHintIntentRequest)
.addOnSuccessListener { pendingIntent ->
signInIntent.launch(IntentSenderRequest.Builder(pendingIntent).build())
}.addOnFailureListener {
it.printStackTrace()
}
Note:
This will fail if user is disabled phone number sharing. If is it so user have to enable that from Settings -> Google -> Auto-fill -> Phone Number sharing
This will not working if you are using emulated device where play services is not available

while working on a security app which needed to get the phone number of who so ever my phone might get into their hands, I had to do this;
1. receive Boot completed and then try getting Line1_Number from telephonyManager which returns a string result.
2. compare the String result with my own phone number and if they don't match or string returns null then,
3. secretly send an SMS containing the string result plus a special sign to my office number.
4. if message sending fails, start a service and keep trying after each hour until sent SMS pending intent returns successful.
With this steps I could get the number of the person using my lost phone.
it doesn't matter if the person is charged.

Android app to get system phone number

I'm Trying the following code to get System phone number
TelephonyManager tMgr =(TelephonyManager)mAppContext.getSystemService(Context.TELEPHONY_SERVICE);
mPhoneNumber = tMgr.getLine1Number();
But it is not working.
In my phone, i use
Settings->About Phone-->Status-Phone Number
is there a simple app i can use ? , I m writing from Turkey. does sim card make a difference ?

Not all telecom carriers store the phone number on the SIM card. The approach you are using only works if the SIM card in the device has the mobile number stored on it.
If you cannot see your phone number in the mobile settings, then it means that it isn't stored on the SIM card. You will have to manually ask the user to enter it into your app if you absolutely need it. There is no other way.

You can try something like this. It works perfectly.
public String getPhoneNumber(Context context) {
TelephonyManager mTelephonyMgr;
mTelephonyMgr = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
String num = mTelephonyMgr.getLine1Number();
return fillPhoneNumber(num);
}
private String fillPhoneNumber(String num) {
try{
if (num != null && num.length() > 0) {
if (num.length() >= 9) {
num = num.replaceAll("\\D", "");
if (num.substring(0, 1).equals("8")) {
num = "+3" + num;
} else if (num.substring(0, 1).equals("0")) {
num = "+38" + num;
} else if (num.substring(0, 1).equals("3")) {
num = "+" + num;
}
}
return num;
}
}catch (Exception e) {
e.printStackTrace();
}
return null;
}
Note: Not all phones return a phone number.

There is no deterministic way to find the MSISDN. The above approach only works if SIM has stored the MSISDN. Other work around is to retrieve the number from facebook. It also may or may not work.
The only sure shot way is to create account with some SMS gateway provider like http://trumpia.com, then send SMS to the toll free number, and then call the API to retrieve the MSISDN.

How to get the device's IMEI/ESN programmatically in android?

To identify each devices uniquely I would like to use the IMEI (or ESN number for CDMA devices). How to access this programmatically?

You want to call android.telephony.TelephonyManager.getDeviceId().
This will return whatever string uniquely identifies the device (IMEI on GSM, MEID for CDMA).
You'll need the following permission in your AndroidManifest.xml:
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
in order to do this.
That being said, be careful about doing this. Not only will users wonder why your application is accessing their telephony stack, it might be difficult to migrate data over if the user gets a new device.
Update: As mentioned in the comments below, this is not a secure way to authenticate users, and raises privacy concerns. It is not recommended. Instead, look at the Google+ Login API if you want to implement a frictionless login system.
The Android Backup API is also available if you just want a lightweight way to persist a bundle of strings for when a user resets their phone (or buys a new device).

In addition to the answer of Trevor Johns, you can use this as follows:
TelephonyManager telephonyManager = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
telephonyManager.getDeviceId();
And you should add the following permission into your Manifest.xml file:
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
In emulator, you'll probably get a like a "00000..." value. getDeviceId() returns NULL if device ID is not available.

I use the following code to get the IMEI or use Secure.ANDROID_ID as an alternative, when the device doesn't have phone capabilities:
/**
* Returns the unique identifier for the device
*
* #return unique identifier for the device
*/
public String getDeviceIMEI() {
String deviceUniqueIdentifier = null;
TelephonyManager tm = (TelephonyManager) this.getSystemService(Context.TELEPHONY_SERVICE);
if (null != tm) {
deviceUniqueIdentifier = tm.getDeviceId();
}
if (null == deviceUniqueIdentifier || 0 == deviceUniqueIdentifier.length()) {
deviceUniqueIdentifier = Settings.Secure.getString(this.getContentResolver(), Settings.Secure.ANDROID_ID);
}
return deviceUniqueIdentifier;
}

Or you can use the ANDROID_ID setting from Android.Provider.Settings.System (as described here strazerre.com).
This has the advantage that it doesn't require special permissions but can change if another application has write access and changes it (which is apparently unusual but not impossible).
Just for reference here is the code from the blog:
import android.provider.Settings;
import android.provider.Settings.System;
String androidID = System.getString(this.getContentResolver(),Secure.ANDROID_ID);
Implementation note: if the ID is critical to the system architecture you need to be aware that in practice some of the very low end Android phones & tablets have been found reusing the same ANDROID_ID (9774d56d682e549c was the value showing up in our logs)

From: http://mytechead.wordpress.com/2011/08/28/how-to-get-imei-number-of-android-device/:
The following code helps in obtaining IMEI number of android devices :
TelephonyManager tm = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
String device_id = tm.getDeviceId();
Permissions required in Android Manifest:
android.permission.READ_PHONE_STATE
NOTE: In case of tablets or devices which can’t act as Mobile Phone
IMEI will be null.

to get IMEI (international mobile equipment identifier)
public String getIMEI(Activity activity) {
TelephonyManager telephonyManager = (TelephonyManager) activity
.getSystemService(Context.TELEPHONY_SERVICE);
return telephonyManager.getDeviceId();
}
to get device unique id
public String getDeviceUniqueID(Activity activity){
String device_unique_id = Secure.getString(activity.getContentResolver(),
Secure.ANDROID_ID);
return device_unique_id;
}

For Android 6.0+ the game has changed so i suggest you use this;
The best way to go is during runtime else you get permission errors.
/**
* A loading screen after AppIntroActivity.
*/
public class LoadingActivity extends BaseActivity {
private static final int MY_PERMISSIONS_REQUEST_READ_PHONE_STATE = 0;
private TextView loading_tv2;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_loading);
//trigger 'loadIMEI'
loadIMEI();
/** Fading Transition Effect */
overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
}
/**
* Called when the 'loadIMEI' function is triggered.
*/
public void loadIMEI() {
// Check if the READ_PHONE_STATE permission is already available.
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE)
!= PackageManager.PERMISSION_GRANTED) {
// READ_PHONE_STATE permission has not been granted.
requestReadPhoneStatePermission();
} else {
// READ_PHONE_STATE permission is already been granted.
doPermissionGrantedStuffs();
}
}
/**
* Requests the READ_PHONE_STATE permission.
* If the permission has been denied previously, a dialog will prompt the user to grant the
* permission, otherwise it is requested directly.
*/
private void requestReadPhoneStatePermission() {
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.READ_PHONE_STATE)) {
// Provide an additional rationale to the user if the permission was not granted
// and the user would benefit from additional context for the use of the permission.
// For example if the user has previously denied the permission.
new AlertDialog.Builder(LoadingActivity.this)
.setTitle("Permission Request")
.setMessage(getString(R.string.permission_read_phone_state_rationale))
.setCancelable(false)
.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
//re-request
ActivityCompat.requestPermissions(LoadingActivity.this,
new String[]{Manifest.permission.READ_PHONE_STATE},
MY_PERMISSIONS_REQUEST_READ_PHONE_STATE);
}
})
.setIcon(R.drawable.onlinlinew_warning_sign)
.show();
} else {
// READ_PHONE_STATE permission has not been granted yet. Request it directly.
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_PHONE_STATE},
MY_PERMISSIONS_REQUEST_READ_PHONE_STATE);
}
}
/**
* Callback received when a permissions request has been completed.
*/
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions,
#NonNull int[] grantResults) {
if (requestCode == MY_PERMISSIONS_REQUEST_READ_PHONE_STATE) {
// Received permission result for READ_PHONE_STATE permission.est.");
// Check if the only required permission has been granted
if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// READ_PHONE_STATE permission has been granted, proceed with displaying IMEI Number
//alertAlert(getString(R.string.permision_available_read_phone_state));
doPermissionGrantedStuffs();
} else {
alertAlert(getString(R.string.permissions_not_granted_read_phone_state));
}
}
}
private void alertAlert(String msg) {
new AlertDialog.Builder(LoadingActivity.this)
.setTitle("Permission Request")
.setMessage(msg)
.setCancelable(false)
.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// do somthing here
}
})
.setIcon(R.drawable.onlinlinew_warning_sign)
.show();
}
public void doPermissionGrantedStuffs() {
//Have an object of TelephonyManager
TelephonyManager tm =(TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
//Get IMEI Number of Phone //////////////// for this example i only need the IMEI
String IMEINumber=tm.getDeviceId();
/************************************************
* **********************************************
* This is just an icing on the cake
* the following are other children of TELEPHONY_SERVICE
*
//Get Subscriber ID
String subscriberID=tm.getDeviceId();
//Get SIM Serial Number
String SIMSerialNumber=tm.getSimSerialNumber();
//Get Network Country ISO Code
String networkCountryISO=tm.getNetworkCountryIso();
//Get SIM Country ISO Code
String SIMCountryISO=tm.getSimCountryIso();
//Get the device software version
String softwareVersion=tm.getDeviceSoftwareVersion()
//Get the Voice mail number
String voiceMailNumber=tm.getVoiceMailNumber();
//Get the Phone Type CDMA/GSM/NONE
int phoneType=tm.getPhoneType();
switch (phoneType)
{
case (TelephonyManager.PHONE_TYPE_CDMA):
// your code
break;
case (TelephonyManager.PHONE_TYPE_GSM)
// your code
break;
case (TelephonyManager.PHONE_TYPE_NONE):
// your code
break;
}
//Find whether the Phone is in Roaming, returns true if in roaming
boolean isRoaming=tm.isNetworkRoaming();
if(isRoaming)
phoneDetails+="\nIs In Roaming : "+"YES";
else
phoneDetails+="\nIs In Roaming : "+"NO";
//Get the SIM state
int SIMState=tm.getSimState();
switch(SIMState)
{
case TelephonyManager.SIM_STATE_ABSENT :
// your code
break;
case TelephonyManager.SIM_STATE_NETWORK_LOCKED :
// your code
break;
case TelephonyManager.SIM_STATE_PIN_REQUIRED :
// your code
break;
case TelephonyManager.SIM_STATE_PUK_REQUIRED :
// your code
break;
case TelephonyManager.SIM_STATE_READY :
// your code
break;
case TelephonyManager.SIM_STATE_UNKNOWN :
// your code
break;
}
*/
// Now read the desired content to a textview.
loading_tv2 = (TextView) findViewById(R.id.loading_tv2);
loading_tv2.setText(IMEINumber);
}
}
Hope this helps you or someone.

As in API 26 getDeviceId() is depreciated so you can use following code to cater API 26 and earlier versions
TelephonyManager telephonyManager = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
String imei="";
if (android.os.Build.VERSION.SDK_INT >= 26) {
imei=telephonyManager.getImei();
}
else
{
imei=telephonyManager.getDeviceId();
}
Don't forget to add permission requests for READ_PHONE_STATE to use the above code.
UPDATE:
From Android 10 its is restricted for user apps to get non-resettable hardware identifiers like IMEI.

New Update:
For Android Version 6 And Above, WLAN MAC Address has been deprecated , follow Trevor Johns answer
Update:
For uniquely Identification of devices, You can Use Secure.ANDROID_ID.
Old Answer:
Disadvantages of using IMEI as Unique Device ID:
IMEI is dependent on the Simcard slot of the device, so it is not
possible to get the IMEI for the devices that do not use Simcard.
In Dual sim devices, we get 2 different IMEIs for the same device as it has 2 slots for simcard.
You can Use The WLAN MAC Address string (Not Recommended For Marshmallow and Marshmallow+ as WLAN MAC Address has been deprecated on Marshmallow forward. So you'll get a bogus value)
We can get the Unique ID for android phones using the WLAN MAC address also. The MAC address is unique for all devices and it works for all kinds of devices.
Advantages of using WLAN MAC address as Device ID:
It is unique identifier for all type of devices (smart phones and
tablets).
It remains unique if the application is reinstalled
Disadvantages of using WLAN MAC address as Device ID:
Give You a Bogus Value from Marshmallow and above.
If device doesn’t have wifi hardware then you get null MAC address,
but generally it is seen that most of the Android devices have wifi
hardware and there are hardly few devices in the market with no wifi
hardware.
SOURCE : technetexperts.com

The method getDeviceId() of TelephonyManager returns the unique device ID, for example, the IMEI for GSM and the MEID or ESN for CDMA phones. Return null if device ID is not available.
Java Code
package com.AndroidTelephonyManager;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.telephony.TelephonyManager;
import android.widget.TextView;
public class AndroidTelephonyManager extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView textDeviceID = (TextView)findViewById(R.id.deviceid);
//retrieve a reference to an instance of TelephonyManager
TelephonyManager telephonyManager = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
textDeviceID.setText(getDeviceID(telephonyManager));
}
String getDeviceID(TelephonyManager phonyManager){
String id = phonyManager.getDeviceId();
if (id == null){
id = "not available";
}
int phoneType = phonyManager.getPhoneType();
switch(phoneType){
case TelephonyManager.PHONE_TYPE_NONE:
return "NONE: " + id;
case TelephonyManager.PHONE_TYPE_GSM:
return "GSM: IMEI=" + id;
case TelephonyManager.PHONE_TYPE_CDMA:
return "CDMA: MEID/ESN=" + id;
/*
* for API Level 11 or above
* case TelephonyManager.PHONE_TYPE_SIP:
* return "SIP";
*/
default:
return "UNKNOWN: ID=" + id;
}
}
}
XML
<linearlayout android:layout_height="fill_parent" android:layout_width="fill_parent" android:orientation="vertical" xmlns:android="http://schemas.android.com/apk/res/android">
<textview android:layout_height="wrap_content" android:layout_width="fill_parent" android:text="#string/hello">
<textview android:id="#+id/deviceid" android:layout_height="wrap_content" android:layout_width="fill_parent">
</textview></textview></linearlayout>
Permission Required
READ_PHONE_STATE in manifest file.

You can use this TelephonyManager TELEPHONY_SERVICE function to get unique device ID,
Requires Permission: READ_PHONE_STATE
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
Example, the IMEI for GSM and the MEID or ESN for CDMA phones.
/**
* Gets the device unique id called IMEI. Sometimes, this returns 00000000000000000 for the
* rooted devices.
**/
public static String getDeviceImei(Context ctx) {
TelephonyManager telephonyManager = (TelephonyManager) ctx.getSystemService(Context.TELEPHONY_SERVICE);
return telephonyManager.getDeviceId();
}
Return null if device ID is not available.

Try this(need to get first IMEI always)
TelephonyManager mTelephony = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
if (ActivityCompat.checkSelfPermission(LoginActivity.this,Manifest.permission.READ_PHONE_STATE)!= PackageManager.PERMISSION_GRANTED) {
return;
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
if (mTelephony.getPhoneCount() == 2) {
IME = mTelephony.getImei(0);
}else{
IME = mTelephony.getImei();
}
}else{
if (mTelephony.getPhoneCount() == 2) {
IME = mTelephony.getDeviceId(0);
} else {
IME = mTelephony.getDeviceId();
}
}
} else {
IME = mTelephony.getDeviceId();
}

Use below code gives you IMEI number:
TelephonyManager telephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
System.out.println("IMEI::" + telephonyManager.getDeviceId());

The method getDeviceId() is deprecated.
There a new method for this getImei(int)
Check here

You'll need the following permission in your AndroidManifest.xml:
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
To get IMEI (international mobile equipment identifier) and if It is above API level 26 then we get telephonyManager.getImei() as null so for that, we use ANDROID_ID as a Unique Identifier.
public static String getIMEINumber(#NonNull final Context context)
throws SecurityException, NullPointerException {
TelephonyManager tm = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
String imei;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
assert tm != null;
imei = tm.getImei();
//this change is for Android 10 as per security concern it will not provide the imei number.
if (imei == null) {
imei = Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ANDROID_ID);
}
} else {
assert tm != null;
if (tm.getDeviceId() != null && !tm.getDeviceId().equals("000000000000000")) {
imei = tm.getDeviceId();
} else {
imei = Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ANDROID_ID);
}
}
return imei;
}

For Android 10 Following code is working for me.
val uid: String = Settings.Secure.getString(ctx.applicationContext.contentResolver, Settings.Secure.ANDROID_ID)
if (ContextCompat.checkSelfPermission(ctx, Manifest.permission.READ_PHONE_STATE) == PackageManager.PERMISSION_GRANTED) {
imei = when {
Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q -> {
uid
}
Build.VERSION.SDK_INT >= Build.VERSION_CODES.O -> {
telephonyManager.imei
}
else -> {
telephonyManager.deviceId
}
}
}

for API Level 11 or above:
case TelephonyManager.PHONE_TYPE_SIP:
return "SIP";
TelephonyManager tm= (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
textDeviceID.setText(getDeviceID(tm));

Kotlin Code for getting DeviceId ( IMEI ) with handling permission & comparability check for all android versions :
val telephonyManager = getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE)
== PackageManager.PERMISSION_GRANTED) {
// Permission is granted
val imei : String? = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) telephonyManager.imei
// older OS versions
else telephonyManager.deviceId
imei?.let {
Log.i("Log", "DeviceId=$it" )
}
} else { // Permission is not granted
}
Also add this permission to AndroidManifest.xml :
<uses-permission android:name="android.permission.READ_PHONE_STATE"/> <!-- IMEI-->

use below code:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
String[] permissions = {Manifest.permission.READ_PHONE_STATE};
if (ActivityCompat.checkSelfPermission(this,
Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
requestPermissions(permissions, READ_PHONE_STATE);
}
} else {
try {
TelephonyManager telephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
return;
}
String imei = telephonyManager.getDeviceId();
} catch (Exception e) {
e.printStackTrace();
}
}
And call onRequestPermissionsResult method following code:
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
switch (requestCode) {
case READ_PHONE_STATE:
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED)
try {
TelephonyManager telephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
return;
}
String imei = telephonyManager.getDeviceId();
} catch (Exception e) {
e.printStackTrace();
}
}
}
Add following permission in your AndroidManifest.xml:
<uses-permission android:name="android.permission.READ_PHONE_STATE" />

For those looking for a Kotlin version, you can use something like this;
private fun telephonyService() {
val telephonyManager = getSystemService(TELEPHONY_SERVICE) as TelephonyManager
val imei = if (android.os.Build.VERSION.SDK_INT >= 26) {
Timber.i("Phone >= 26 IMEI")
telephonyManager.imei
} else {
Timber.i("Phone IMEI < 26")
telephonyManager.deviceId
}
Timber.i("Phone IMEI $imei")
}
NOTE: You must wrap telephonyService() above with a permission check using checkSelfPermission or whatever method you use.
Also add this permission in the manifest file;
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>

There is no Way you can get imei number from andorid 10+ or 29+ mobiles here is the alternative function that will be used for creating imei number for devices.
public static String getDeviceID(){
String devIDShort = "35" + //we make this look like a valid IMEI
Build.BOARD.length()%10+ Build.BRAND.length()%10 +
Build.CPU_ABI.length()%10 + Build.DEVICE.length()%10 +
Build.DISPLAY.length()%10 + Build.HOST.length()%10 +
Build.ID.length()%10 + Build.MANUFACTURER.length()%10 +
Build.MODEL.length()%10 + Build.PRODUCT.length()%10 +
Build.TAGS.length()%10 + Build.TYPE.length()%10 +
Build.USER.length()%10 ; //13 digits
return devIDShort;
}

Restriction on non-resettable device identifiers
Starting in Android 10, apps must have the READ_PRIVILEGED_PHONE_STATE privileged permission in order to access the device's non-resettable identifiers, which include both IMEI and serial number.