diff --git a/src/data/move.ts b/src/data/move.ts
index fba5b853f4a..cb6e91a2362 100644
--- a/src/data/move.ts
+++ b/src/data/move.ts
@@ -1903,7 +1903,7 @@ export class AddSubstituteAttr extends MoveEffectAttr {
   }
 
   getCondition(): MoveConditionFunc {
-    return (user, target, move) => !user.getTag(SubstituteTag) && user.hp > Math.floor(user.getMaxHp() * this.hpCost) && user.getMaxHp() > 1;
+    return (user, target, move) => !user.getTag(SubstituteTag) && user.hp > (this.roundUp ? Math.ceil(user.getMaxHp() * this.hpCost) : Math.floor(user.getMaxHp() * this.hpCost)) && user.getMaxHp() > 1;
   }
 
   /**