diff --git a/server/szurubooru/search/configs/post_search_config.py b/server/szurubooru/search/configs/post_search_config.py
index fc98e550..f985d66b 100644
--- a/server/szurubooru/search/configs/post_search_config.py
+++ b/server/szurubooru/search/configs/post_search_config.py
@@ -304,6 +304,17 @@ class PostSearchConfig(BaseSearchConfig):
                     ["creation-date", "creation-time", "date", "time"],
                     search_util.create_date_filter(model.Post.creation_time),
                 ),
+                (
+                    [
+                        "file-last-modified-time",
+                        "file-modified",
+                        "source-modified",
+                        "flmt",
+                    ],
+                    search_util.create_date_filter(
+                        model.Post.file_last_modified_time
+                    ),
+                ),
                 (
                     [
                         "last-edit-date",
@@ -390,6 +401,15 @@ class PostSearchConfig(BaseSearchConfig):
                     ["creation-date", "creation-time", "date", "time"],
                     (model.Post.creation_time, self.SORT_DESC),
                 ),
+                (
+                    [
+                        "file-last-modified-time",
+                        "file-modified",
+                        "source-modified",
+                        "flmt",
+                    ],
+                    (model.Post.file_last_modified_time, self.SORT_DESC),
+                ),
                 (
                     [
                         "last-edit-date",