diff --git a/bodsdata.py b/bodsdata.py
index a932349..e541713 100644
--- a/bodsdata.py
+++ b/bodsdata.py
@@ -694,8 +694,10 @@ def download_files_s3(source, s3_path_pattern, latest=False, bucket="bodsdata-oo
     bucket = get_s3_bucket(bucket)
     items = []
 
+    if not s3_path_pattern.startswith("^"): s3_path_pattern = f"^{s3_path_pattern}"
+
     for item in bucket.objects.all():
-        if re.search(s3_path_pattern, item.key):
+        if item.key.startswith(s3_path_pattern):
             items.append(item.key)
 
     items.sort()