Co-signer can help build credit

Dear Terry,
My sister bought a car and I am the co-signer. I need to clear my credit history and I got a chance to do it this week, and that means my sister's car is in my report. She is making payments on time, but I need to pay off that car. My sister just got the car this year in February, and she is trying to build credit. She does not have bad credit, she just doesn't have any credit. Can I pay off her car, and how much this will help her credit?
-- Ana

Dear Ana,
Paying off the loan early and after seven months of payments will help raise your sister's credit score. Will it be enough that she could get another car loan without a co-signer? It depends on other factors such as income. But it's a start toward building a good credit history.

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