diff --git a/changes/bug20646 b/changes/bug20646
new file mode 100644
index 0000000000..42e319ffcb
--- /dev/null
+++ b/changes/bug20646
@@ -0,0 +1,5 @@
+  o Minor bugfix (util)
+    - When finishing writing a file to disk, if we were about to replace the
+      file with the temporary file created before and we fail to replace it,
+      remove the temporary file so it doesn't stay on disk. Closes #20646;
+      bugfix on tor-0.2.0.7-alpha; Patch by fk.
diff --git a/src/common/util.c b/src/common/util.c
index cb5f12821e..3421d117b0 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -2601,6 +2601,14 @@ finish_writing_to_file_impl(open_file_t *file_data, int abort_write)
 
   if (file_data->rename_on_close) {
     tor_assert(file_data->tempname && file_data->filename);
+    if (!abort_write) {
+      tor_assert(strcmp(file_data->filename, file_data->tempname));
+      if (replace_file(file_data->tempname, file_data->filename)) {
+        log_warn(LD_FS, "Error replacing \"%s\": %s", file_data->filename,
+                 strerror(errno));
+        abort_write = r = -1;
+      }
+    }
     if (abort_write) {
       int res = unlink(file_data->tempname);
       if (res != 0) {
@@ -2609,13 +2617,6 @@ finish_writing_to_file_impl(open_file_t *file_data, int abort_write)
                  file_data->tempname, strerror(errno));
         r = -1;
       }
-    } else {
-      tor_assert(strcmp(file_data->filename, file_data->tempname));
-      if (replace_file(file_data->tempname, file_data->filename)) {
-        log_warn(LD_FS, "Error replacing \"%s\": %s", file_data->filename,
-                 strerror(errno));
-        r = -1;
-      }
     }
   }