diff --git a/qutebrowser/completion/models/base.py b/qutebrowser/completion/models/base.py
index 8fc88e54a..cb589ce38 100644
--- a/qutebrowser/completion/models/base.py
+++ b/qutebrowser/completion/models/base.py
@@ -133,13 +133,3 @@ class BaseCompletionModel(QStandardItemModel):
         Override QAbstractItemModel::sort.
         """
         raise NotImplementedError
-
-    def custom_filter(self, pattern, row, parent):
-        """Custom filter.
-
-        Args:
-            pattern: The current filter pattern.
-            row: The row to accept or reject in the filter.
-            parent: The parent item QModelIndex.
-        """
-        raise NotImplementedError
diff --git a/qutebrowser/completion/models/sortfilter.py b/qutebrowser/completion/models/sortfilter.py
index ab0a60242..19c3d61d2 100644
--- a/qutebrowser/completion/models/sortfilter.py
+++ b/qutebrowser/completion/models/sortfilter.py
@@ -140,20 +140,17 @@ class CompletionFilterModel(QSortFilterProxyModel):
         if parent == QModelIndex() or not self.pattern:
             return True
 
-        try:
-            return self.srcmodel.custom_filter(self.pattern, row, parent)
-        except NotImplementedError:
-            for col in self.srcmodel.columns_to_filter:
-                idx = self.srcmodel.index(row, col, parent)
-                if not idx.isValid():
-                    # No entries in parent model
-                    continue
-                data = self.srcmodel.data(idx)
-                if not data:
-                    continue
-                elif self.pattern_re.search(data):
-                    return True
-            return False
+        for col in self.srcmodel.columns_to_filter:
+            idx = self.srcmodel.index(row, col, parent)
+            if not idx.isValid():
+                # No entries in parent model
+                continue
+            data = self.srcmodel.data(idx)
+            if not data:
+                continue
+            elif self.pattern_re.search(data):
+                return True
+        return False
 
     def intelligentLessThan(self, lindex, rindex):
         """Custom sorting implementation.