If you have a very limited credit history or a not-so-good credit record, you may want to ask someone to co-sign when you need a student loan. Having a co-signer may increase your chances of loan approval and may help you qualify for a lower interest rate. However, you can’t ask just anyone; being a co-signer is a serious responsibility.

Consider these traits of a good co-signer. Ask someone who:

1. You trust. You must be open and honest with your co-signer about your credit history and problems. “Your co-signer needs to be able to evaluate just how risky a proposition it is to co-sign for you,” says Navy Federal's Aaron Aggerwal, Assistant Vice President of Education Lending.

2. Is a constant presence in your life. Usually, this means a family member. You’ll have a responsibility to each other until your student loan is paid off, so it shouldn’t be someone you’ll lose touch with.

3. Can afford to make the payments if you can’t. Your co-signer is legally responsible to make payments if you don’t. You should choose someone who would be able to make the payments without ruining their own finances.

4. Has a good credit score. Your co-signer’s credit score can help you qualify for a student loan and a good interest rate. “Student loans typically require you to reapply each school year. This means that your interest rate may rise if your co-signer's credit score drops,” Aggerwal notes. “On the other hand, having a co-signer with an excellent credit score can save you a significant amount of money over the life of the loan.”

5. Doesn’t have a lot of debt (and/or has a high income). Lenders look at a co-signer’s debt-to-income ratio. They want to know that your co-signer could afford to pay all of his or her own debts as well as yours if you default on payments.

6. Is savvy enough to understand what’s on the line. Your co-signer should understand all the terms, responsibilities and liabilities of the loan. The co-signer’s credit score may be affected, too. If you miss payments or chronically pay late, it will be reflected in your co-signer’s credit history.

7. Has stable work and residence histories. “Lenders look for a co-signer they will be able to contact easily should the need arise,” Aggerwal says.

8. Wants the best for you. Your co-signer should be supportive of your use of the loan and agree that it’s a positive and worthwhile step for you to take.

Asking someone to co-sign a loan for you is not a matter to be taken lightly. If you know someone with the right qualifications who’s willing to do it, it can be a very effective way for you to improve your credit record—as long as you make all your payments on time. After all, you wouldn’t want to damage your relationship with such a cherished person!