diff --git a/serverless.yml b/serverless.yml
index 7465d9b4..c8fadfca 100644
--- a/serverless.yml
+++ b/serverless.yml
@@ -31,7 +31,7 @@ provider:
     ENGINE_SQS_URL:
       Ref: EngineQueue
     # hardcode the categorisation queue for now as it's created in terraform
-    CATEGORISATION_SQS_URL: https://sqs.eu-west-2.amazonaws.com/337213553626/categorisation-queue-dev
+    CATEGORISATION_SQS_URL: "https://sqs.eu-west-2.amazonaws.com/337213553626/categorisation-queue-dev"
 
 plugins:
   - serverless-python-requirements