diff --git a/moto/backend_index.py b/moto/backend_index.py
index 5f57542fb..fc1508f28 100644
--- a/moto/backend_index.py
+++ b/moto/backend_index.py
@@ -114,7 +114,7 @@ backend_url_patterns = [
     ),
     (
         "meteringmarketplace",
-        re.compile("https?://metering.marketplace.(.+).amazonaws.com"),
+        re.compile("https?://metering\\.marketplace.(.+).amazonaws.com"),
     ),
     ("meteringmarketplace", re.compile("https?://aws-marketplace.(.+).amazonaws.com")),
     ("mq", re.compile("https?://mq\\.(.+)\\.amazonaws\\.com")),