Your credit card can be a super weapon

Defective merchandise. Shoddy plumbing work. A car repair shop that didn't fix the problem. Undisclosed and unfair fees. Shipments that never arrived. Even careful consumers sometimes run into problems.

Consumers' Checkbook often advises using a credit card when buying products and services, when possible. That's because using plastic is more than just a convenient way to pay; it also provides incredibly strong protections against most lousy-service scenarios and companies that sell faulty goods.

The genesis of these protections is the federal Fair Credit Billing Act, which protects you from fraud by requiring credit card companies—not consumers — to deal with fraudulent charges. The law also provides important protections against billing errors.

What many consumers don't know is that the law also requires credit card companies to give their customers the opportunity to dispute charges — and withhold payments — for goods and services that weren't delivered as promised.

When you request a "chargeback," the seller can protest. It may claim you made no effort to resolve the matter, refused to return goods that you say are unsatisfactory, or that the goods are exactly what you ordered.

In Checkbook's experience — feedback from surveys of consumers and staff who have requested chargebacks — credit card companies are far more likely to side with consumers than businesses during these disputes.

Because credit card issuers want to keep their customers happy, the protections they provide are, in practice, even broader than your rights under the law. For example, while the law states that you have to contest a charge within 60 days of receiving a bill, most banks that work with Visa and MasterCard give their customers 120 days to contest it, and on a case-by-case basis usually allow even more time.

Before disputing a charge, give the offending company a reasonable chance to make things right. Chargebacks are serious problems for businesses that get hit with them.

If you can't work out the problem, ask your credit card company for its chargeback procedures. Often, you can contest charges on its website. Some banks still require customers to submit requests in writing and mail in documentation (this is most common with debit cards).

Even if you already paid your credit card bill in full, you can still contest the charge. During the time that the credit card company investigates, the questionable charge is removed from your outstanding balance, and you are not required to pay it or the portion of your balance, or any interest, until the dispute is resolved.

Although Checkbook finds that credit card companies typically side with consumers, sometimes they do deny chargeback claims, even when sellers clearly were in the wrong. Sometimes this is due to customers having signed contracts that include causes such as "buyer beware" or "all sales final." But if your request for a chargeback is denied, don't give up. In Checkbook's experience, a second or third appeal can result in a revised ruling in the consumer's favor.

Don't take advantage. Just as credit card companies keep a lookout for companies that abuse their customers, they also keep track of cardholders who dispute too many charges.