diff --git a/index.html b/index.html
index 2bb0093668..ceb9fe17aa 100644
--- a/index.html
+++ b/index.html
@@ -57,6 +57,7 @@
     <script>
       window.GIT_COMMIT = <%- gitCommit %>;
       window.ASSET_MANIFEST = <%- assetManifest %>;
+      window.WS_URL = <%- wsUrl %>;
       window.BOOTSTRAP_CONFIG = {
         gameEnv: <%- gameEnv %>,
       };
diff --git a/src/client/LobbySocket.ts b/src/client/LobbySocket.ts
index e664329b7d..cf21f675b8 100644
--- a/src/client/LobbySocket.ts
+++ b/src/client/LobbySocket.ts
@@ -54,7 +54,7 @@ export class PublicLobbySocket {
       }
 
       const protocol = window.location.protocol === "https:" ? "wss:" : "ws:";
-      const wsUrl = `${protocol}//${window.location.host}${this.workerPath}/lobbies`;
+      const wsUrl = `${protocol}//${window.WS_URL}/${this.workerPath}/lobbies`;
 
       this.ws = new WebSocket(wsUrl);
       this.wsAttemptCounted = false;
diff --git a/src/client/Main.ts b/src/client/Main.ts
index 6f828698a8..14633539b7 100644
--- a/src/client/Main.ts
+++ b/src/client/Main.ts
@@ -163,6 +163,7 @@ function updateAccountNavButton(userMeResponse: UserMeResponse | false) {
 declare global {
   interface Window {
     GIT_COMMIT: string;
+    WS_URL: string;
     turnstile: any;
     adsEnabled: boolean;
     PageOS: {
diff --git a/src/client/Transport.ts b/src/client/Transport.ts
index 1641b614ab..6a3097798f 100644
--- a/src/client/Transport.ts
+++ b/src/client/Transport.ts
@@ -324,7 +324,7 @@ export class Transport {
   ) {
     this.startPing();
     this.killExistingSocket();
-    const wsHost = window.location.host;
+    const wsHost = window.WS_URL;
     const wsProtocol = window.location.protocol === "https:" ? "wss:" : "ws:";
     const workerPath = this.lobbyConfig.serverConfig.workerPath(
       this.lobbyConfig.gameID,
diff --git a/src/server/RenderHtml.ts b/src/server/RenderHtml.ts
index f7898f3dae..9691eda0d7 100644
--- a/src/server/RenderHtml.ts
+++ b/src/server/RenderHtml.ts
@@ -26,6 +26,7 @@ export async function renderHtmlContent(htmlPath: string): Promise<string> {
     backgroundImageUrl: buildAssetUrl("images/background.webp", assetManifest),
     desktopLogoImageUrl: buildAssetUrl("images/OpenFront.webp", assetManifest),
     mobileLogoImageUrl: buildAssetUrl("images/OF.webp", assetManifest),
+    wsUrl: JSON.stringify(`${process.env.SUBDOMAIN}.${process.env.DOMAIN}`),
   });
 }
 
diff --git a/vite.config.ts b/vite.config.ts
index e535448961..c34d12ebcd 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -101,6 +101,7 @@ export default defineConfig(({ mode }) => {
               inject: {
                 data: {
                   gitCommit: JSON.stringify("DEV"),
+                  wsUrl: JSON.stringify("localhost:9000"),
                   ...htmlAssetData,
                 },
               },