diff --git a/src/indexer.py b/src/indexer.py
index 1375a03..57efd81 100644
--- a/src/indexer.py
+++ b/src/indexer.py
@@ -214,19 +214,24 @@ def get_recent_keys(mbox: mailbox.Maildir, days: int) -> set:
     recent = set()
     maildir_root = mbox._path  # type: ignore[attr-defined]
 
-    for key in mbox.keys():
-        # Maildir keys are stored under cur/ or new/ — try both
-        for subdir in ("cur", "new"):
-            file_path = os.path.join(maildir_root, subdir, key)
+    for subdir in ("cur", "new"):
+        subdir_path = os.path.join(maildir_root, subdir)
+        try:
+            filenames = os.listdir(subdir_path)
+        except OSError:
+            continue
+
+        for filename in filenames:
+            file_path = os.path.join(subdir_path, filename)
             try:
-                # Single stat() call instead of isfile() + getmtime()
                 if os.stat(file_path).st_mtime >= cutoff_ts:
+                    # Maildir keys are the filename, but the actual file on disk
+                    # often has a suffix (like ":2,S"). mailbox.Maildir treats
+                    # the part BEFORE the first colon as the key.
+                    key = filename.split(":")[0] if ":" in filename else filename
                     recent.add(key)
-            except FileNotFoundError:
-                continue  # try next subdir
             except OSError:
-                pass
-            break  # found the file (stat succeeded or non-ENOENT error), stop trying subdirs
+                continue
 
     return recent