Fees can make an otherwise affordable loan expensive. But some fees, such as the annual maintenance fee charged on a home equity line of credit (HELOC), can actually lower the costs of your loan, depending on how you intend to use your HELOC.

Many of the fees associated with a HELOC should be avoided, such as an application fee, an appraisal fee, and a "non-usage" fee charged for leaving the money in your line of credit untouched. (The non-usage fee is particularly disagreeable, since one of the main benefits of a HELOC is its usefulness as a safety net in case of emergencies.) But the decision to choose a HELOC with an annual fee depends on whether it offers a better interest rate than non-fee loans and how frequently you plan on withdrawing money.

To help you decide, head to BankingMyWay.com's home equity section and enter your ZIP code for a list of rate offers in your area. Residents of North Carolina, for instance, can apply for a $50,000 HELOC from Fifth Third Bank ( FITB) with an interest rate of 3.75%, as long as they are willing to pay a $65 annual fee. Alternatively, they could apply for the same-sized line of credit from Southern Community Bank and Trust ( SCMF) or Citizens South Bank ( CSBC) at interest rates of 5.0% and 6.0%, respectively, and not have to pay any annual rate.

The next step is to figure out whether the lower interest rate is worth the extra fee you're paying. There's only a 1.25 percentage point difference in rates between the HELOCs offered by the Fifth Third Bank ($65 fee) and the Southern Community Bank and Trust (no fee). If you withdrew $25,000 on the first day of your line of credit and didn't repay it for a full year, the $65 fee would save you $312.50 in extra interest ($25,000 x 1.25% = $312.50). However, if you choose instead to use your HELOC only for emergencies and make repaying the balance a priority, you may not incur enough interest charges to warrant the $65 annual fee.

Best advice: If you expect make regular use of the money in your line of credit, the annual fee may be worth it. Just be sure to crunch the numbers to see if the interest savings are more than the cost of the fee.

For more on home equity, check these recent BankingMyWay articles:

"Five tips on finding a home equity line of credit"

"Home Equity Debt: How to Deal with Your Debt"