diff --git a/packages/replay/src/replay.ts b/packages/replay/src/replay.ts
index 30ccda422544..0d3d40fb94dc 100644
--- a/packages/replay/src/replay.ts
+++ b/packages/replay/src/replay.ts
@@ -27,6 +27,7 @@ import { clearSession } from './session/clearSession';
 import { loadOrCreateSession } from './session/loadOrCreateSession';
 import { saveSession } from './session/saveSession';
 import { shouldRefreshSession } from './session/shouldRefreshSession';
+
 import type {
   AddEventResult,
   AddUpdateCallback,
@@ -294,6 +295,12 @@ export class ReplayContainer implements ReplayContainerInterface {
 
     logInfoNextTick('[Replay] Starting replay in session mode', this._options._experiments.traceInternals);
 
+    // Required as user activity is initially set in
+    // constructor, so if `start()` is called after
+    // session idle expiration, a replay will not be
+    // created due to an idle timeout.
+    this._updateUserActivity();
+
     const session = loadOrCreateSession(
       {
         maxReplayDuration: this._options.maxReplayDuration,
diff --git a/packages/replay/test/integration/beforeAddRecordingEvent.test.ts b/packages/replay/test/integration/beforeAddRecordingEvent.test.ts
index e6800f4e53d0..035d566def43 100644
--- a/packages/replay/test/integration/beforeAddRecordingEvent.test.ts
+++ b/packages/replay/test/integration/beforeAddRecordingEvent.test.ts
@@ -2,8 +2,7 @@ import * as SentryCore from '@sentry/core';
 import type { Transport } from '@sentry/types';
 import * as SentryUtils from '@sentry/utils';
 
-// eslint-disable-next-line deprecation/deprecation
-import type { Replay } from '../../src';
+import type { replayIntegration } from '../../src/integration';
 import type { ReplayContainer } from '../../src/replay';
 import { clearSession } from '../../src/session/clearSession';
 import { createPerformanceEntries } from '../../src/util/createPerformanceEntries';
@@ -24,8 +23,7 @@ type MockTransportSend = jest.MockedFunction<Transport['send']>;
 
 describe('Integration | beforeAddRecordingEvent', () => {
   let replay: ReplayContainer;
-  // eslint-disable-next-line deprecation/deprecation
-  let integration: Replay;
+  let integration: ReturnType<typeof replayIntegration>;
   let mockTransportSend: MockTransportSend;
   let mockSendReplayRequest: jest.SpyInstance<any>;
   let domHandler: DomHandler;
diff --git a/packages/replay/test/integration/start.test.ts b/packages/replay/test/integration/start.test.ts
new file mode 100644
index 000000000000..7fbef9f8149c
--- /dev/null
+++ b/packages/replay/test/integration/start.test.ts
@@ -0,0 +1,53 @@
+import { getClient } from '@sentry/core';
+import type { Transport } from '@sentry/types';
+
+import { DEFAULT_FLUSH_MIN_DELAY, SESSION_IDLE_EXPIRE_DURATION } from '../../src/constants';
+import type { replayIntegration } from '../../src/integration';
+import type { ReplayContainer } from '../../src/replay';
+import { BASE_TIMESTAMP } from '../index';
+import { resetSdkMock } from '../mocks/resetSdkMock';
+import { useFakeTimers } from '../utils/use-fake-timers';
+
+useFakeTimers();
+
+describe('Integration | start', () => {
+  let replay: ReplayContainer;
+  let integration: ReturnType<typeof replayIntegration>;
+
+  beforeEach(async () => {
+    ({ replay, integration } = await resetSdkMock({
+      replayOptions: {
+        stickySession: false,
+      },
+      sentryOptions: {
+        replaysSessionSampleRate: 0.0,
+      },
+    }));
+
+    const mockTransport = getClient()?.getTransport()?.send as jest.MockedFunction<Transport['send']>;
+    mockTransport?.mockClear();
+    jest.runAllTimers();
+    await new Promise(process.nextTick);
+  });
+
+  afterEach(async () => {
+    integration.stop();
+
+    jest.runAllTimers();
+    await new Promise(process.nextTick);
+    jest.setSystemTime(new Date(BASE_TIMESTAMP));
+  });
+
+  it('sends replay when calling `start()` after [SESSION_IDLE_EXPIRE_DURATION]ms', async () => {
+    jest.advanceTimersByTime(SESSION_IDLE_EXPIRE_DURATION + 1);
+
+    integration.start();
+
+    jest.advanceTimersByTime(DEFAULT_FLUSH_MIN_DELAY);
+    await new Promise(process.nextTick);
+
+    expect(replay).toHaveLastSentReplay({
+      recordingPayloadHeader: { segment_id: 0 },
+    });
+  });
+});
diff --git a/packages/replay/test/integration/stop.test.ts b/packages/replay/test/integration/stop.test.ts
index 35bc44f0c80f..de0d212de8e9 100644
--- a/packages/replay/test/integration/stop.test.ts
+++ b/packages/replay/test/integration/stop.test.ts
@@ -1,8 +1,7 @@
 import * as SentryUtils from '@sentry/utils';
 
-// eslint-disable-next-line deprecation/deprecation
-import type { Replay } from '../../src';
 import { WINDOW } from '../../src/constants';
+import type { replayIntegration } from '../../src/integration';
 import type { ReplayContainer } from '../../src/replay';
 import { clearSession } from '../../src/session/clearSession';
 import { addEvent } from '../../src/util/addEvent';
@@ -18,8 +17,7 @@ type MockRunFlush = jest.MockedFunction<ReplayContainer['_runFlush']>;
 
 describe('Integration | stop', () => {
   let replay: ReplayContainer;
-  // eslint-disable-next-line deprecation/deprecation
-  let integration: Replay;
+  let integration: ReturnType<typeof replayIntegration>;
   const prevLocation = WINDOW.location;
 
   const { record: mockRecord } = mockRrweb();