Debt settlement programs can leave late marks and collection accounts on a person's credit report, lowering credit scores by 100-200 points.If a person's accounts have already been sent to a collection agency, in this case, their credit score has already taken a hit and probably won't go down much more. As each debt gets settled one by one, a person's credit score could start to improve, but there's no guarantee on that.If your number-one concern is to maintain a high credit score, don't use debt settlement. Consumer credit counseling and debt consolidation are two debt relief options that could improve a person's credit score.