Kotlin Google Sign-In Not Returning Account Fix

If you’re integrating Google Sign-In in your Kotlin Android app and facing the issue where GoogleSignIn.getLastSignedInAccount(context) returns null even after a successful login, you’re not alone. This common error can frustrate many developers, especially those new to the integration process.

In this comprehensive guide, we’ll go through:

• Why this issue happens
• How to fix Google Sign-In not returning account in Kotlin
• Full working code example
• Common mistakes and debugging tips

Why GoogleSignIn.getLastSignedInAccount() Returns Null

This method returns null if:

1. User is not signed in (you never called signInIntent)
2. Sign-in failed silently
3. Missing or incorrect configuration in your Google API Console or google-services.json
4. Wrong request codes or misused callbacks
5. Missing GoogleSignInOptions when trying to retrieve the account

Solution: Proper Google Sign-In Integration in Kotlin

Step 1: Add Required Dependencies

Make sure your build.gradle has the correct dependencies:

implementation 'com.google.android.gms:play-services-auth:21.0.0'=

Step 2: Configure GoogleSignInOptions

val gso = GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
    .requestEmail()
    .build()

Step 3: Initialize GoogleSignInClient

val googleSignInClient = GoogleSignIn.getClient(this, gso)

Step 4: Start Sign-In Intent

val signInIntent = googleSignInClient.signInIntent
startActivityForResult(signInIntent, RC_SIGN_IN)

Where RC_SIGN_IN is a constant (e.g., private val RC_SIGN_IN = 1001)

Step 5: Handle Sign-In Result

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)

    if (requestCode == RC_SIGN_IN) {
        val task = GoogleSignIn.getSignedInAccountFromIntent(data)
        try {
            val account = task.getResult(ApiException::class.java)
            Log.d("GoogleSignIn", "Signed in as: ${account?.email}")
        } catch (e: ApiException) {
            Log.e("GoogleSignIn", "Sign in failed", e)
        }
    }
}

How to Retrieve Account After Sign-In

To get the account info later (e.g., in onCreate()), you must not sign out and call:

val account = GoogleSignIn.getLastSignedInAccount(this)
if (account != null) {
    Log.d("GoogleAccount", "User email: ${account.email}")
} else {
    Log.d("GoogleAccount", "No signed-in user found")
}

Make sure this line is only called after the user has successfully signed in.

Common Mistakes

Debugging Tips

• Add logs in onActivityResult to ensure you’re getting a valid intent.
• Check Google Developer Console: Is the SHA-1 of your debug/release key added?
• Make sure your app package name in Firebase/Google Console matches your app.
• Clean and rebuild your project.
• Test on real device with actual Google account.

Full Example: Kotlin Activity with Google Sign-In

class LoginActivity : AppCompatActivity() {

    private val RC_SIGN_IN = 1001
    private lateinit var googleSignInClient: GoogleSignInClient

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_login)

        val gso = GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
            .requestEmail()
            .build()

        googleSignInClient = GoogleSignIn.getClient(this, gso)

        findViewById<Button>(R.id.sign_in_button).setOnClickListener {
            val signInIntent = googleSignInClient.signInIntent
            startActivityForResult(signInIntent, RC_SIGN_IN)
        }

        val account = GoogleSignIn.getLastSignedInAccount(this)
        if (account != null) {
            Log.d("LoginActivity", "Already signed in as: ${account.email}")
        }
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        if (requestCode == RC_SIGN_IN) {
            val task = GoogleSignIn.getSignedInAccountFromIntent(data)
            try {
                val account = task.getResult(ApiException::class.java)
                Log.d("LoginActivity", "Signed in as: ${account?.email}")
                // Proceed to next activity
            } catch (e: ApiException) {
                Log.e("LoginActivity", "Sign in failed", e)
            }
        }
    }
}