diff --git a/store/sqlstore/post_store.go b/store/sqlstore/post_store.go
index 03ee58888e..044ee6ca27 100644
--- a/store/sqlstore/post_store.go
+++ b/store/sqlstore/post_store.go
@@ -2840,8 +2840,23 @@ func (s *SqlPostStore) updateThreadAfterReplyDeletion(transaction *sqlxTxWrapper
 			}
 		}
 
+		lastReplyAtSubquery := sq.Select("COALESCE(MAX(CreateAt), 0)").
+			From("Posts").
+			Where(sq.Eq{
+				"RootId":   rootId,
+				"DeleteAt": 0,
+			})
+
+		lastReplyCountSubquery := sq.Select("Count(*)").
+			From("Posts").
+			Where(sq.Eq{
+				"RootId":   rootId,
+				"DeleteAt": 0,
+			})
+
 		updateQueryString, updateArgs, err := updateQuery.
-			Set("ReplyCount", sq.Expr("ReplyCount - 1")).
+			Set("LastReplyAt", lastReplyAtSubquery).
+			Set("ReplyCount", lastReplyCountSubquery).
 			Where(sq.And{
 				sq.Eq{"PostId": rootId},
 				sq.Gt{"ReplyCount": 0},
diff --git a/store/storetest/post_store.go b/store/storetest/post_store.go
index 98efff5321..2489847905 100644
--- a/store/storetest/post_store.go
+++ b/store/storetest/post_store.go
@@ -979,6 +979,74 @@ func testPostStoreDelete(t *testing.T, ss store.Store) {
 		_, err = ss.Post().Get(context.Background(), rootPost2.Id, model.GetPostsOptions{}, "", map[string]bool{})
 		require.NoError(t, err)
 	})
+
+	t.Run("thread with multiple replies, update thread last reply at", func(t *testing.T) {
+		// Create a root post
+		rootPost1, err := ss.Post().Save(&model.Post{
+			ChannelId: model.NewId(),
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+		})
+		require.NoError(t, err)
+
+		// Reply to that root post
+		replyPost1, err := ss.Post().Save(&model.Post{
+			ChannelId: rootPost1.ChannelId,
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+			RootId:    rootPost1.Id,
+		})
+		require.NoError(t, err)
+
+		// Reply to that root post a second time
+		replyPost2, err := ss.Post().Save(&model.Post{
+			ChannelId: rootPost1.ChannelId,
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+			RootId:    rootPost1.Id,
+		})
+		require.NoError(t, err)
+
+		// Reply to that root post a third time
+		replyPost3, err := ss.Post().Save(&model.Post{
+			ChannelId: rootPost1.ChannelId,
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+			RootId:    rootPost1.Id,
+		})
+		require.NoError(t, err)
+
+		thread, err := ss.Thread().Get(rootPost1.Id)
+		require.NoError(t, err)
+		require.Equal(t, replyPost3.CreateAt, thread.LastReplyAt)
+
+		// Delete the reply previous to last
+		err = ss.Post().Delete(replyPost2.Id, model.GetMillis(), "")
+		require.NoError(t, err)
+
+		thread, err = ss.Thread().Get(rootPost1.Id)
+		require.NoError(t, err)
+		// last reply at should be unchanged
+		require.Equal(t, replyPost3.CreateAt, thread.LastReplyAt)
+
+		// Delete the last reply
+		err = ss.Post().Delete(replyPost3.Id, model.GetMillis(), "")
+		require.NoError(t, err)
+
+		thread, err = ss.Thread().Get(rootPost1.Id)
+		require.NoError(t, err)
+		// last reply at should have changed
+		require.Equal(t, replyPost1.CreateAt, thread.LastReplyAt)
+
+		// Delete the last reply
+		err = ss.Post().Delete(replyPost1.Id, model.GetMillis(), "")
+		require.NoError(t, err)
+
+		thread, err = ss.Thread().Get(rootPost1.Id)
+		require.NoError(t, err)
+		// last reply at should be 0
+		require.Equal(t, int64(0), thread.LastReplyAt)
+	})
 }
 
 func testPostStorePermDelete1Level(t *testing.T, ss store.Store) {