diff --git a/google/auth/app_engine.py b/google/auth/app_engine.py
index d20ddf6..566475e 100644
--- a/google/auth/app_engine.py
+++ b/google/auth/app_engine.py
@@ -87,6 +87,13 @@
         self.token, self.expiry = token, expiry
 
     @property
+    def service_account_email(self):
+        """The service account email."""
+        if self._service_account_id is None:
+            self._service_account_id = app_identity.get_service_account_name()
+        return self._service_account_id
+
+    @property
     def requires_scopes(self):
         """Checks if the credentials requires scopes.
 
diff --git a/google/auth/compute_engine/credentials.py b/google/auth/compute_engine/credentials.py
index cd215c5..5729956 100644
--- a/google/auth/compute_engine/credentials.py
+++ b/google/auth/compute_engine/credentials.py
@@ -93,6 +93,15 @@
             raise exceptions.RefreshError(exc)
 
     @property
+    def service_account_email(self):
+        """The service account email.
+
+        .. note: This is not guaranteed to be set until :meth`refresh` has been
+            called.
+        """
+        return self._service_account_email
+
+    @property
     def requires_scopes(self):
         """False: Compute Engine credentials can not be scoped."""
         return False
diff --git a/google/oauth2/service_account.py b/google/oauth2/service_account.py
index 6159301..24c852b 100644
--- a/google/oauth2/service_account.py
+++ b/google/oauth2/service_account.py
@@ -232,6 +232,11 @@
             subject=self._service_account_email)
 
     @property
+    def service_account_email(self):
+        """The service account email."""
+        return self._service_account_email
+
+    @property
     def requires_scopes(self):
         """Checks if the credentials requires scopes.