diff --git a/keyserver/src/responders/user-responders.js b/keyserver/src/responders/user-responders.js
--- a/keyserver/src/responders/user-responders.js
+++ b/keyserver/src/responders/user-responders.js
@@ -565,7 +565,22 @@
     );
   }
 
-  // 9. Complete login with call to `processSuccessfulLogin(...)`.
+  // 9. Try to double-write SIWE account info to the Identity service
+  const rustAPI = await getRustAPI();
+  if (identityKeys && signedIdentityKeysBlob) {
+    handleAsyncPromise(
+      rustAPI.loginUserWallet(
+        userID,
+        identityKeys.primaryIdentityPublicKeys.ed25519,
+        siweMessage.toMessage(),
+        signature,
+        signedIdentityKeysBlob,
+        JSON.stringify(socialProof),
+      ),
+    );
+  }
+
+  // 10. Complete login with call to `processSuccessfulLogin(...)`.
   return await processSuccessfulLogin({
     viewer,
     input,