diff --git a/keyserver/src/creators/account-creator.js b/keyserver/src/creators/account-creator.js
--- a/keyserver/src/creators/account-creator.js
+++ b/keyserver/src/creators/account-creator.js
@@ -111,10 +111,13 @@
     INSERT INTO users(id, username, hash, creation_time)
     VALUES ${[newUserRow]}
   `;
+
+  const { primaryIdentityPublicKey } = request;
   const [userViewerData] = await Promise.all([
     createNewUserCookie(id, {
       platformDetails: request.platformDetails,
       deviceToken,
+      primaryIdentityPublicKey,
     }),
     deleteCookie(viewer.cookieID),
     dbQuery(newUserQuery),
diff --git a/lib/types/account-types.js b/lib/types/account-types.js
--- a/lib/types/account-types.js
+++ b/lib/types/account-types.js
@@ -52,6 +52,7 @@
   +calendarQuery?: ?CalendarQuery,
   +deviceTokenUpdateRequest?: ?DeviceTokenUpdateRequest,
   +platformDetails: PlatformDetails,
+  +primaryIdentityPublicKey?: ?string,
 };
 
 export type RegisterResponse = {