diff --git a/src/step.ts b/src/step.ts
index f1f7888..dfec414 100644
--- a/src/step.ts
+++ b/src/step.ts
@@ -32,7 +32,7 @@ export interface Action {
   toToken: Token
   toAddress?: string
 
-  slippage: number
+  slippage?: number
 }
 
 // ESTIMATE