diff --git a/ts/session/disappearing_messages/index.ts b/ts/session/disappearing_messages/index.ts
index 8c54de7ca..f74783417 100644
--- a/ts/session/disappearing_messages/index.ts
+++ b/ts/session/disappearing_messages/index.ts
@@ -422,6 +422,34 @@ export async function checkForExpireUpdateInContentMessage(
   return expireUpdate;
 }
 
+/**
+ * Checks if an outgoing message is meant to disappear and if so trigger the timer
+ */
+export function checkForExpiringOutgoingMessage(message: MessageModel, location?: string) {
+  const convo = message.getConversation();
+  const expireTimer = message.getExpireTimer();
+  const expirationType = message.getExpirationType();
+
+  if (
+    convo &&
+    expirationType &&
+    expireTimer > 0 &&
+    Boolean(message.getExpirationStartTimestamp()) === false
+  ) {
+    const expirationMode = changeToDisappearingConversationMode(convo, expirationType, expireTimer);
+
+    if (expirationMode !== 'off') {
+      message.set({
+        expirationStartTimestamp: setExpirationStartTimestamp(
+          expirationMode,
+          message.get('sent_at'),
+          location
+        ),
+      });
+    }
+  }
+}
+
 // TODO legacy messages support will be removed in a future release
 export function getMessageReadyToDisappear(
   conversationModel: ConversationModel,
diff --git a/ts/session/sending/MessageSentHandler.ts b/ts/session/sending/MessageSentHandler.ts
index 504e4a96c..6de155f42 100644
--- a/ts/session/sending/MessageSentHandler.ts
+++ b/ts/session/sending/MessageSentHandler.ts
@@ -2,10 +2,7 @@ import _ from 'lodash';
 import { Data } from '../../data/data';
 import { SignalService } from '../../protobuf';
 import { PnServer } from '../apis/push_notification_api';
-import {
-  changeToDisappearingConversationMode,
-  setExpirationStartTimestamp,
-} from '../disappearing_messages';
+import { checkForExpiringOutgoingMessage } from '../disappearing_messages';
 import { OpenGroupVisibleMessage } from '../messages/outgoing/visibleMessage/OpenGroupVisibleMessage';
 import { RawMessage } from '../types';
 import { UserUtils } from '../utils';
@@ -130,29 +127,7 @@ async function handleMessageSentSuccess(
     sent_at: effectiveTimestamp,
   });
 
-  const convo = fetchedMessage.getConversation();
-  const expireTimer = fetchedMessage.getExpireTimer();
-  const expirationType = fetchedMessage.getExpirationType();
-
-  if (
-    convo &&
-    expirationType &&
-    expireTimer > 0 &&
-    Boolean(fetchedMessage.getExpirationStartTimestamp()) === false
-  ) {
-    const expirationMode = changeToDisappearingConversationMode(convo, expirationType, expireTimer);
-
-    // NOTE starting disappearing messages timer for all outbound messages
-    if (expirationMode !== 'off') {
-      fetchedMessage.set({
-        expirationStartTimestamp: setExpirationStartTimestamp(
-          expirationMode,
-          fetchedMessage.get('sent_at'),
-          'handleMessageSentSuccess'
-        ),
-      });
-    }
-  }
+  checkForExpiringOutgoingMessage(fetchedMessage, 'handleMessageSentSuccess');
 
   await fetchedMessage.commit();
   fetchedMessage.getConversation()?.updateLastMessage();
diff --git a/ts/test/session/unit/disappearing_messages/DisappearingMessage_test.ts b/ts/test/session/unit/disappearing_messages/DisappearingMessage_test.ts
index 36e267ad8..5bc1b6984 100644
--- a/ts/test/session/unit/disappearing_messages/DisappearingMessage_test.ts
+++ b/ts/test/session/unit/disappearing_messages/DisappearingMessage_test.ts
@@ -8,6 +8,7 @@ import {
   changeToDisappearingConversationMode,
   changeToDisappearingMessageType,
   checkForExpireUpdateInContentMessage,
+  checkForExpiringOutgoingMessage,
   setExpirationStartTimestamp,
 } from '../../../../session/disappearing_messages';
 import {
@@ -22,6 +23,7 @@ import {
   generateDisappearingVisibleMessage,
   generateFakeExpirationTimerUpdate,
   generateFakeIncomingPrivateMessage,
+  generateFakeOutgoingPrivateMessage,
   generateVisibleMessage,
 } from '../../../test-utils/utils';
 
@@ -469,6 +471,91 @@ describe('DisappearingMessage', () => {
     });
   });
 
+  describe('checkForExpiringInOutgoingMessage', () => {
+    it('if the message is supposed to disappear then the expirationStartTimestamp should be set to the sent_at value', async () => {
+      const conversation = new ConversationModel({
+        ...conversationArgs,
+        id: ourNumber,
+      } as any);
+      const message = generateFakeOutgoingPrivateMessage(conversation.get('id'));
+      message.set({
+        expirationType: 'deleteAfterRead',
+        expireTimer: 300,
+        sent_at: GetNetworkTime.getNowWithNetworkOffset(),
+      });
+      Sinon.stub(message, 'getConversation').returns(conversation);
+
+      checkForExpiringOutgoingMessage(message, 'unit tests');
+
+      expect(message.getExpirationStartTimestamp(), 'it should be defined').to.not.be.undefined;
+      expect(
+        isValidUnixTimestamp(message.getExpirationStartTimestamp()),
+        'it should be a valid unix timestamp'
+      ).to.be.true;
+      expect(message.getExpirationStartTimestamp(), 'it should equal the sent_at value').to.equal(
+        message.get('sent_at')
+      );
+    });
+    it('if there is no expireTimer then the expirationStartTimestamp should be undefined', async () => {
+      const conversation = new ConversationModel({
+        ...conversationArgs,
+        id: ourNumber,
+      } as any);
+      const message = generateFakeOutgoingPrivateMessage(conversation.get('id'));
+      message.set({
+        expirationType: 'deleteAfterRead',
+        sent_at: GetNetworkTime.getNowWithNetworkOffset(),
+      });
+      Sinon.stub(message, 'getConversation').returns(conversation);
+
+      checkForExpiringOutgoingMessage(message, 'unit tests');
+
+      expect(message.getExpirationStartTimestamp(), 'it should be undefined').to.be.undefined;
+    });
+    it('if there is no expirationType then the expirationStartTimestamp should be undefined', async () => {
+      const conversation = new ConversationModel({
+        ...conversationArgs,
+        id: ourNumber,
+      } as any);
+      const message = generateFakeOutgoingPrivateMessage(conversation.get('id'));
+      message.set({
+        expireTimer: 300,
+        sent_at: GetNetworkTime.getNowWithNetworkOffset(),
+      });
+      Sinon.stub(message, 'getConversation').returns(conversation);
+
+      checkForExpiringOutgoingMessage(message, 'unit tests');
+
+      expect(message.getExpirationStartTimestamp(), 'it should be undefined').to.be.undefined;
+    });
+    it('if expirationStartTimestamp is already defined then it should not have changed', async () => {
+      const now = GetNetworkTime.getNowWithNetworkOffset();
+      const conversation = new ConversationModel({
+        ...conversationArgs,
+        id: ourNumber,
+      } as any);
+      const message = generateFakeOutgoingPrivateMessage(conversation.get('id'));
+      message.set({
+        expirationType: 'deleteAfterRead',
+        expireTimer: 300,
+        sent_at: now,
+        expirationStartTimestamp: now + 10000,
+      });
+      Sinon.stub(message, 'getConversation').returns(conversation);
+
+      checkForExpiringOutgoingMessage(message, 'unit tests');
+
+      expect(message.getExpirationStartTimestamp(), 'it should be defined').to.not.be.undefined;
+      expect(
+        isValidUnixTimestamp(message.getExpirationStartTimestamp()),
+        'it should be a valid unix timestamp'
+      ).to.be.true;
+      expect(message.getExpirationStartTimestamp(), 'it should equal its original value').to.equal(
+        now + 10000
+      );
+    });
+  });
+
   describe('conversation.ts', () => {
     describe('updateExpireTimer', () => {
       it('if the coversation is public it should return false', async () => {
diff --git a/ts/test/test-utils/utils/message.ts b/ts/test/test-utils/utils/message.ts
index a446149ea..5b1f2e14f 100644
--- a/ts/test/test-utils/utils/message.ts
+++ b/ts/test/test-utils/utils/message.ts
@@ -107,6 +107,15 @@ export function generateFakeIncomingPrivateMessage(): MessageModel {
   });
 }
 
+export function generateFakeOutgoingPrivateMessage(pubkey?: string): MessageModel {
+  const convoId = pubkey || TestUtils.generateFakePubKeyStr();
+  return new MessageModel({
+    conversationId: convoId,
+    source: convoId,
+    type: 'outgoing',
+  });
+}
+
 export function generateFakeIncomingOpenGroupMessageV4({
   id,
   reactions,