diff --git a/app/javascript/packages/countdown-element/index.spec.ts b/app/javascript/packages/countdown-element/index.spec.ts
index 939b87f6dfd..5666ce65051 100644
--- a/app/javascript/packages/countdown-element/index.spec.ts
+++ b/app/javascript/packages/countdown-element/index.spec.ts
@@ -102,4 +102,17 @@ describe('CountdownElement', () => {
 
     expect(element.textContent).to.equal('0 minutes and 2 seconds');
   });
+
+  describe('#start', () => {
+    it('is idempotent', () => {
+      const element = createElement({ startImmediately: 'false' });
+
+      sinon.spy(element, 'setTimeRemaining');
+
+      element.start();
+      element.start();
+
+      expect(clock.countTimers()).to.equal(1);
+    });
+  });
 });
diff --git a/app/javascript/packages/countdown-element/index.ts b/app/javascript/packages/countdown-element/index.ts
index e42fdc7d6e5..a107fc05540 100644
--- a/app/javascript/packages/countdown-element/index.ts
+++ b/app/javascript/packages/countdown-element/index.ts
@@ -42,6 +42,7 @@ export class CountdownElement extends HTMLElement {
   }
 
   start(): void {
+    this.stop();
     this.setTimeRemaining();
     this.#pollIntervalId = window.setInterval(() => this.setTimeRemaining(), this.updateInterval);
   }