diff --git a/prism/src/explicit/rewards/MDPRewardsSimple.java b/prism/src/explicit/rewards/MDPRewardsSimple.java
index fdaeb7eb..fe7d85f3 100644
--- a/prism/src/explicit/rewards/MDPRewardsSimple.java
+++ b/prism/src/explicit/rewards/MDPRewardsSimple.java
@@ -106,6 +106,8 @@ public class MDPRewardsSimple implements MDPRewards
 	@Override
 	public double getStateReward(int s)
 	{
+		if (stateRewards == null)
+			return 0.0;
 		return stateRewards.get(s);
 	}