diff --git a/lib/geocoder/lookups/base.rb b/lib/geocoder/lookups/base.rb
index 43f7cc55f02ff34eb5f7adc571150c225134118e..66bc9efe001f1cd76ffe1eec779257415c83049f 100644
--- a/lib/geocoder/lookups/base.rb
+++ b/lib/geocoder/lookups/base.rb
@@ -252,6 +252,9 @@ module Geocoder
         elsif response.code.to_i == 429
           raise_error(Geocoder::OverQueryLimitError) ||
             warn("Geocoding API error: 429 Too Many Requests")
+        elsif response.code.to_i == 503
+          raise_error(Geocoder::ServiceUnavailable) ||
+            warn("Geocoding API error: 503 Service Unavailable")
         end
       end