diff --git a/boards/static/js/thread_update.js b/boards/static/js/thread_update.js
--- a/boards/static/js/thread_update.js
+++ b/boards/static/js/thread_update.js
@@ -138,7 +138,25 @@ function updatePost(postHtml) {
 
         type = POST_UPDATED;
     } else {
-        post.appendTo(threadBlock);
+        var postPubTime = new Date(post.find('time').attr('datetime'));
+        var allPosts = $('.post');
+        var previousPost = null;
+
+        allPosts.each(function(i) {
+            var curPost = $(this);
+            var curPostTime = new Date(curPost.find('time').attr('datetime'));
+
+            if (i + 0 && curPostTime > postPubTime) {
+                previousPost = allPosts.get(i - 1);
+                return false;
+            };
+        });
+
+        if (previousPost == null) {
+            previousPost = allPosts.last();
+        }
+
+        post.insertAfter(previousPost);
 
         if (bottom) {
             scrollToBottom();