diff --git a/src/AddThreepid.js b/src/AddThreepid.js
index 8f19815210..dde0fbcbc9 100644
--- a/src/AddThreepid.js
+++ b/src/AddThreepid.js
@@ -20,6 +20,10 @@ import MatrixClientPeg from './MatrixClientPeg';
 import { _t } from './languageHandler';
 import IdentityAuthClient from './IdentityAuthClient';
 
+function getIdServerDomain() {
+    return MatrixClientPeg.get().idBaseUrl.split("://")[1];
+}
+
 /**
  * Allows a user to add a third party identifier to their homeserver and,
  * optionally, the identity servers.
@@ -155,7 +159,6 @@ export default class AddThreepid {
      * the request failed.
      */
     async checkEmailLinkClicked() {
-        const identityServerDomain = MatrixClientPeg.get().idBaseUrl.split("://")[1];
         try {
             if (await MatrixClientPeg.get().doesServerSupportSeparateAddAndBind()) {
                 if (this.bind) {
@@ -164,7 +167,7 @@ export default class AddThreepid {
                     await MatrixClientPeg.get().bindThreePid({
                         sid: this.sessionId,
                         client_secret: this.clientSecret,
-                        id_server: identityServerDomain,
+                        id_server: getIdServerDomain(),
                         id_access_token: identityAccessToken,
                     });
                 } else {
@@ -177,7 +180,7 @@ export default class AddThreepid {
                 await MatrixClientPeg.get().addThreePid({
                     sid: this.sessionId,
                     client_secret: this.clientSecret,
-                    id_server: identityServerDomain,
+                    id_server: getIdServerDomain(),
                 }, this.bind);
             }
         } catch (err) {