diff --git a/lib/Echidna/Exec.hs b/lib/Echidna/Exec.hs
index fb04d3580..f76691897 100644
--- a/lib/Echidna/Exec.hs
+++ b/lib/Echidna/Exec.hs
@@ -54,7 +54,7 @@ classifyError = \case
   StackLimitExceeded   -> RevertE
   StackUnderrun        -> IllegalE
   BadJumpDestination   -> IllegalE
-  IllegalOverflow      -> IllegalE
+  IllegalOverflow      -> RevertE
   _                    -> UnknownE
 
 -- | Extracts the 'Query' if there is one.