diff --git a/Telegram/SourceFiles/data/data_replies_list.cpp b/Telegram/SourceFiles/data/data_replies_list.cpp
index 492db196ed..dedcb57f27 100644
--- a/Telegram/SourceFiles/data/data_replies_list.cpp
+++ b/Telegram/SourceFiles/data/data_replies_list.cpp
@@ -860,7 +860,13 @@ std::optional<int> RepliesList::computeUnreadCountLocally(
 		MsgId afterId) const {
 	Expects(afterId >= _inboxReadTillId);
 
-	const auto wasUnreadCountAfter = _unreadCount.current();
+	const auto currentUnreadCountAfter = _unreadCount.current();
+	const auto startingMarkingAsRead = (currentUnreadCountAfter == 0)
+		&& (_inboxReadTillId == 1)
+		&& (afterId > 1);
+	const auto wasUnreadCountAfter = startingMarkingAsRead
+		? _fullCount.current().value_or(0)
+		: currentUnreadCountAfter;
 	const auto readTillId = std::max(afterId, _rootId);
 	const auto wasReadTillId = _inboxReadTillId;
 	const auto backLoaded = (_skippedBefore == 0);