diff --git a/packages/app/src/pages/sign-in.tsx b/packages/app/src/pages/sign-in.tsx
index 324482d..2af4f53 100644
--- a/packages/app/src/pages/sign-in.tsx
+++ b/packages/app/src/pages/sign-in.tsx
@@ -4,6 +4,7 @@ import * as ui from "@exosphere/client/ui.css";
 export function SignIn() {
   const handle = useSignal("");
   const error = useSignal("");
+  const loading = useSignal(false);
 
   const submit = (e: Event) => {
     e.preventDefault();
@@ -12,6 +13,7 @@ export function SignIn() {
       error.value = "Please enter your handle.";
       return;
     }
+    loading.value = true;
     // Full page redirect to initiate OAuth flow
     window.location.href = `/api/oauth/login?handle=${encodeURIComponent(value)}`;
   };
@@ -42,8 +44,8 @@ export function SignIn() {
 
           {error.value && <p class={ui.errorText}>{error.value}</p>}
 
-          <button type="submit" class={ui.button}>
-            Sign in
+          <button type="submit" class={ui.button} disabled={loading.value}>
+            {loading.value ? "Signing in…" : "Sign in"}
           </button>
         </form>
       </div>