diff --git a/README.md b/README.md
index b25cc0a93f3ca18799f84e85d0e7dc85754ee80a..46ffa9a9bbb2c741cb3234fa2b019aa54c191d4c 100644
--- a/README.md
+++ b/README.md
@@ -996,6 +996,7 @@ The raise-able exceptions are:
     Geocoder::RequestDenied
     Geocoder::InvalidRequest
     Geocoder::InvalidApiKey
+    Geocoder::ServiceUnavailable
 
 Note that not all lookups support all exceptions.