diff --git a/src/PostgREST/Error.hs b/src/PostgREST/Error.hs
index d1a33f3d0..cdd12761e 100644
--- a/src/PostgREST/Error.hs
+++ b/src/PostgREST/Error.hs
@@ -54,7 +54,8 @@ httpStatus (H.TxError (P.ErroneousResult codeBS _ _ _)) =
     '0':'9':_ -> HT.status500 -- triggered action exception
     '0':'L':_ -> HT.status403 -- invalid grantor
     '0':'P':_ -> HT.status403 -- invalid role specification
-    '2':'3':_ -> HT.status409 -- Integrity Constraint Violation
+    "23503" -> HT.status409 -- foreign_key_violation
+    "23505" -> HT.status409 -- unique_violation
     '2':'5':_ -> HT.status500 -- invalid tx state
     '2':'8':_ -> HT.status403 -- invalid auth specification
     '2':'D':_ -> HT.status500 -- invalid tx termination