diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java b/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java
index 8de99a1bb..b7ca28184 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java
@@ -1129,7 +1129,7 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
             zkSecretParams, zkProfileOperations, batchIdentityCheckExecutor),
         new ProvisioningController(rateLimiters, provisioningManager),
         new RegistrationController(accountsManager, phoneVerificationTokenManager, registrationLockVerificationManager,
-            rateLimiters),
+            rateLimiters, registrationFraudChecker),
         new RemoteConfigController(remoteConfigsManager, config.getRemoteConfigConfiguration().globalConfig(), clock),
         new SecureStorageController(storageCredentialsGenerator),
         new SecureValueRecovery2Controller(svr2CredentialsGenerator, accountsManager),
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/controllers/RegistrationController.java b/service/src/main/java/org/whispersystems/textsecuregcm/controllers/RegistrationController.java
index efd8c0a2f..f64cddd33 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/controllers/RegistrationController.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/controllers/RegistrationController.java
@@ -34,6 +34,8 @@ import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Optional;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.whispersystems.textsecuregcm.auth.BasicAuthorizationHeader;
 import org.whispersystems.textsecuregcm.auth.PhoneVerificationTokenManager;
 import org.whispersystems.textsecuregcm.auth.RegistrationLockVerificationManager;
@@ -44,6 +46,7 @@ import org.whispersystems.textsecuregcm.entities.RegistrationLockFailure;
 import org.whispersystems.textsecuregcm.entities.RegistrationRequest;
 import org.whispersystems.textsecuregcm.limits.RateLimiters;
 import org.whispersystems.textsecuregcm.metrics.UserAgentTagUtil;
+import org.whispersystems.textsecuregcm.spam.RegistrationFraudChecker;
 import org.whispersystems.textsecuregcm.storage.Account;
 import org.whispersystems.textsecuregcm.storage.AccountsManager;
 import org.whispersystems.textsecuregcm.storage.DeviceCapability;
@@ -69,16 +72,21 @@ public class RegistrationController {
   private final PhoneVerificationTokenManager phoneVerificationTokenManager;
   private final RegistrationLockVerificationManager registrationLockVerificationManager;
   private final RateLimiters rateLimiters;
+  private final RegistrationFraudChecker registrationFraudChecker;
+
+  private static final Logger logger = LoggerFactory.getLogger(RegistrationController.class);
 
   public RegistrationController(final AccountsManager accounts,
                                 final PhoneVerificationTokenManager phoneVerificationTokenManager,
                                 final RegistrationLockVerificationManager registrationLockVerificationManager,
-                                final RateLimiters rateLimiters) {
+                                final RateLimiters rateLimiters,
+                                final RegistrationFraudChecker registrationFraudChecker) {
 
     this.accounts = accounts;
     this.phoneVerificationTokenManager = phoneVerificationTokenManager;
     this.registrationLockVerificationManager = registrationLockVerificationManager;
     this.rateLimiters = rateLimiters;
+    this.registrationFraudChecker = registrationFraudChecker;
   }
 
   @POST
@@ -125,8 +133,8 @@ public class RegistrationController {
 
     rateLimiters.getRegistrationLimiter().validate(number);
 
-    final PhoneVerificationRequest.VerificationType verificationType = phoneVerificationTokenManager.verify(
-        requestContext, number, registrationRequest);
+    final PhoneVerificationRequest.VerificationType verificationType =
+        phoneVerificationTokenManager.verify(requestContext, number, registrationRequest);
 
     final Optional<Account> existingAccount = accounts.getByE164(number);
 
@@ -169,6 +177,14 @@ public class RegistrationController {
             registrationRequest.deviceActivationRequest().pniPqLastResortPreKey()),
         userAgent);
 
+    if (verificationType == PhoneVerificationRequest.VerificationType.SESSION) {
+      try {
+        registrationFraudChecker.handleVerificationCompleted(registrationRequest.sessionId(), account);
+      } catch (final Exception e) {
+        logger.warn("Failed to notify fraud checker of completed verification session", e);
+      }
+    }
+
     Metrics.counter(ACCOUNT_CREATED_COUNTER_NAME, Tags.of(UserAgentTagUtil.getPlatformTag(userAgent),
             Tag.of(COUNTRY_CODE_TAG_NAME, Util.getCountryCode(number)),
             Tag.of(REGION_CODE_TAG_NAME, Util.getRegion(number)),
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/spam/RegistrationFraudChecker.java b/service/src/main/java/org/whispersystems/textsecuregcm/spam/RegistrationFraudChecker.java
index d30c93527..6a6034390 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/spam/RegistrationFraudChecker.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/spam/RegistrationFraudChecker.java
@@ -8,6 +8,7 @@ import jakarta.ws.rs.container.ContainerRequestContext;
 import java.util.Optional;
 import org.whispersystems.textsecuregcm.entities.UpdateVerificationSessionRequest;
 import org.whispersystems.textsecuregcm.registration.VerificationSession;
+import org.whispersystems.textsecuregcm.storage.Account;
 
 public interface RegistrationFraudChecker {
 
@@ -47,6 +48,14 @@ public interface RegistrationFraudChecker {
       final VerificationSession verificationSession,
       final String e164);
 
+  /**
+   * Handles a completed verification session resulting in a registration.
+   *
+   * @param verificationSessionId The ID of the verification session that resulted in a completed registration
+   * @param createdAccount        The account created at the end of the verification session
+   */
+  void handleVerificationCompleted(final String verificationSessionId, final Account createdAccount);
+
   static RegistrationFraudChecker noop() {
     return new RegistrationFraudChecker() {
 
@@ -64,6 +73,10 @@ public interface RegistrationFraudChecker {
 
         return VerificationCheck.DEFAULT;
       }
+
+      @Override
+      public void handleVerificationCompleted(final String verificationSessionId, final Account createdAccount) {
+      }
     };
   }
 }
diff --git a/service/src/test/java/org/whispersystems/textsecuregcm/controllers/RegistrationControllerTest.java b/service/src/test/java/org/whispersystems/textsecuregcm/controllers/RegistrationControllerTest.java
index 4cd9b7135..9203b54d3 100644
--- a/service/src/test/java/org/whispersystems/textsecuregcm/controllers/RegistrationControllerTest.java
+++ b/service/src/test/java/org/whispersystems/textsecuregcm/controllers/RegistrationControllerTest.java
@@ -11,6 +11,7 @@ import static org.mockito.ArgumentMatchers.argThat;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -75,6 +76,7 @@ import org.whispersystems.textsecuregcm.mappers.ImpossiblePhoneNumberExceptionMa
 import org.whispersystems.textsecuregcm.mappers.NonNormalizedPhoneNumberExceptionMapper;
 import org.whispersystems.textsecuregcm.mappers.RateLimitExceededExceptionMapper;
 import org.whispersystems.textsecuregcm.registration.RegistrationServiceClient;
+import org.whispersystems.textsecuregcm.spam.RegistrationFraudChecker;
 import org.whispersystems.textsecuregcm.spam.RegistrationRecoveryChecker;
 import org.whispersystems.textsecuregcm.storage.Account;
 import org.whispersystems.textsecuregcm.storage.AccountsManager;
@@ -109,6 +111,7 @@ class RegistrationControllerTest {
       RegistrationRecoveryPasswordsManager.class);
   private final RegistrationRecoveryChecker registrationRecoveryChecker = mock(RegistrationRecoveryChecker.class);
   private final RateLimiters rateLimiters = mock(RateLimiters.class);
+  private final RegistrationFraudChecker registrationFraudChecker = mock(RegistrationFraudChecker.class);
 
   private final RateLimiter registrationLimiter = mock(RateLimiter.class);
 
@@ -123,7 +126,7 @@ class RegistrationControllerTest {
           new RegistrationController(accountsManager,
               new PhoneVerificationTokenManager(phoneNumberIdentifiers, registrationServiceClient,
                   registrationRecoveryPasswordsManager, registrationRecoveryChecker),
-              registrationLockVerificationManager, rateLimiters))
+              registrationLockVerificationManager, rateLimiters, registrationFraudChecker))
       .build();
 
   @BeforeEach
@@ -138,6 +141,8 @@ class RegistrationControllerTest {
 
       return invocation.getArgument(0);
     });
+
+    reset(registrationFraudChecker);
   }
 
   @Test
@@ -497,9 +502,14 @@ class RegistrationControllerTest {
         .target("/v1/registration")
         .request()
         .header(HttpHeaders.AUTHORIZATION, AuthHelper.getProvisioningAuthHeader(NUMBER, PASSWORD));
+
     try (Response response = request.post(Entity.json(requestJson("sessionId")))) {
       assertEquals(200, response.getStatus());
     }
+
+    verify(registrationFraudChecker)
+        .handleVerificationCompleted(Base64.getEncoder().encodeToString("sessionId".getBytes(StandardCharsets.UTF_8)),
+            account);
   }
 
   @ParameterizedTest