diff --git a/boards/abstracts/settingsmanager.py b/boards/abstracts/settingsmanager.py
--- a/boards/abstracts/settingsmanager.py
+++ b/boards/abstracts/settingsmanager.py
@@ -1,3 +1,4 @@
+from boards import settings
 from boards.models import Tag
 from boards.models.thread import FAV_THREAD_NO_UPDATES
 
@@ -126,14 +127,17 @@ class SettingsManager:
 
     def add_or_read_fav_thread(self, opening_post):
         threads = self.get_fav_threads()
-        thread = opening_post.get_thread()
-        # Don't check for new posts if the thread is archived already
-        if thread.is_archived():
-            last_id = FAV_THREAD_NO_UPDATES
-        else:
-            last_id = thread.get_replies().last().id
-        threads[str(opening_post.id)] = last_id
-        self.set_setting(SETTING_FAVORITE_THREADS, threads)
+
+        max_fav_threads = settings.get_int('View', 'MaxFavoriteThreads')
+        if (str(opening_post.id) in threads) or (len(threads) < max_fav_threads):
+            thread = opening_post.get_thread()
+            # Don't check for new posts if the thread is archived already
+            if thread.is_archived():
+                last_id = FAV_THREAD_NO_UPDATES
+            else:
+                last_id = thread.get_replies().last().id
+            threads[str(opening_post.id)] = last_id
+            self.set_setting(SETTING_FAVORITE_THREADS, threads)
 
     def del_fav_thread(self, opening_post):
         threads = self.get_fav_threads()
diff --git a/boards/config/default_settings.ini b/boards/config/default_settings.ini
--- a/boards/config/default_settings.ini
+++ b/boards/config/default_settings.ini
@@ -28,6 +28,7 @@ DefaultImageViewer = simple
 LastRepliesCount = 3
 ThreadsPerPage = 3
 ImagesPerPageGallery = 20
+MaxFavoriteThreads = 20
 
 [Storage]
 # Enable archiving threads instead of deletion when the thread limit is reached