diff --git a/src/ConversationList/ConversationItemModel.vala b/src/ConversationList/ConversationItemModel.vala
index d299b9cfe..406a7dbf7 100644
--- a/src/ConversationList/ConversationItemModel.vala
+++ b/src/ConversationList/ConversationItemModel.vala
@@ -248,4 +248,10 @@ public class Mail.ConversationItemModel : GLib.Object {
 
         return has_flag;
     }
+
+    public static int compare_func (Object a, Object b) {
+        var item1 = (ConversationItemModel) a;
+        var item2 = (ConversationItemModel) b;
+        return (int)(item2.timestamp - item1.timestamp);
+    }
 }
diff --git a/src/ConversationList/ConversationList.vala b/src/ConversationList/ConversationList.vala
index 3656d09c1..281c806a0 100644
--- a/src/ConversationList/ConversationList.vala
+++ b/src/ConversationList/ConversationList.vala
@@ -52,7 +52,6 @@ public class Mail.ConversationList : Gtk.Box {
         folder_info_flags = new Gee.HashMap<string, Camel.FolderInfoFlags> ();
         threads = new Gee.HashMap<string, Camel.FolderThread> ();
         list_store = new ConversationListStore ();
-        list_store.set_sort_func (thread_sort_function);
         list_store.set_filter_func (filter_function);
 
         list_box = new VirtualizingListBox () {
@@ -414,7 +413,7 @@ public class Mail.ConversationList : Gtk.Box {
     private void add_conversation_item (Camel.FolderInfoFlags folder_info_flags, Camel.FolderThreadNode child, Camel.FolderThread thread, string service_uid) {
         var item = new ConversationItemModel (folder_info_flags, child, thread, service_uid);
         conversations[child.message.uid] = item;
-        list_store.add (item);
+        list_store.insert_sorted (item, ConversationItemModel.compare_func);
     }
 
     private static bool filter_function (GLib.Object obj) {
@@ -426,10 +425,6 @@ public class Mail.ConversationList : Gtk.Box {
         }
     }
 
-    private static int thread_sort_function (ConversationItemModel item1, ConversationItemModel item2) {
-        return (int)(item2.timestamp - item1.timestamp);
-    }
-
     public void mark_read_selected_messages () {
         var selected_rows = list_box.get_selected_rows ();
         foreach (var row in selected_rows) {
diff --git a/src/ConversationList/ConversationListStore.vala b/src/ConversationList/ConversationListStore.vala
index ccf31704c..0ee613cd9 100644
--- a/src/ConversationList/ConversationListStore.vala
+++ b/src/ConversationList/ConversationListStore.vala
@@ -27,10 +27,9 @@ public class Mail.ConversationListStore : ListModel, Object {
     private GLib.Sequence<ConversationItemModel> data = new GLib.Sequence<ConversationItemModel> ();
     private uint last_position = uint.MAX;
     private GLib.SequenceIter<ConversationItemModel>? last_iter;
-    private unowned GLib.CompareDataFunc<ConversationItemModel> compare_func;
     private unowned RowVisibilityFunc filter_func;
 
-    public GLib.Type get_item_type () {
+    private GLib.Type get_item_type () {
         return typeof (GLib.Object);
     }
 
@@ -38,14 +37,10 @@ public class Mail.ConversationListStore : ListModel, Object {
         return data.get_length ();
     }
 
-    public GLib.Object? get_item (uint index) {
+    private GLib.Object? get_item (uint index) {
         return get_item_internal (index);
     }
 
-    public GLib.Object? get_item_unfiltered (uint index) {
-        return get_item_internal (index, true);
-    }
-
     private GLib.Object? get_item_internal (uint index, bool unfiltered = false) {
         GLib.SequenceIter<ConversationItemModel>? iter = null;
 
@@ -81,12 +76,8 @@ public class Mail.ConversationListStore : ListModel, Object {
         }
     }
 
-    public void add (ConversationItemModel data) {
-        if (compare_func != null) {
-            this.data.insert_sorted (data, compare_func);
-        } else {
-            this.data.append (data);
-        }
+    public void insert_sorted (ConversationItemModel item, CompareDataFunc<Object> compare_func) {
+        data.insert_sorted (item, compare_func);
 
         last_iter = null;
         last_position = uint.MAX;
@@ -108,10 +99,6 @@ public class Mail.ConversationListStore : ListModel, Object {
         last_position = uint.MAX;
     }
 
-    public void set_sort_func (GLib.CompareDataFunc<ConversationItemModel> function) {
-        this.compare_func = function;
-    }
-
     public void set_filter_func (RowVisibilityFunc? function) {
         filter_func = function;
     }
@@ -175,14 +162,14 @@ public class Mail.ConversationListStore : ListModel, Object {
         return -1;
     }
 
-    public int get_index_of_unfiltered (GLib.Object? item) {
+    private int get_index_of_unfiltered (GLib.Object? item) {
         if (item == null) {
             return -1;
         }
 
         var length = get_n_items ();
         for (int i = 0; i < length; i++) {
-            if (item == get_item_unfiltered (i)) {
+            if (item == get_item_internal (i, true)) {
                 return i;
             }
         }