diff --git a/backend/requirements.txt b/backend/requirements.txt
index c4d9df1..bcccac7 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -3,7 +3,7 @@ uvicorn[standard]
 sqlmodel
 psycopg2-binary
 anthropic
-policyengine-uk-compiled==0.65.0
+policyengine-uk-compiled==0.66.0
 pandas
 pyyaml
 httpx