Credit card © Fancy, Veer, Corbis

Want to know how to become a credit card hacker? No, I’m not talking about becoming a member of Project Blitzkrieg and doing something illegal that could land you in the slammer.

What could keep you and your plastic free of unnecessary fees and charges, though, is by becoming a master of credit card hacks. In this case, a “hack” is a loophole — a sneaky strategy, if you will — in your credit card that allows you to get the most out of the rewards and savings they provide. From the grocery store, to paying off debt, to the grocery store again, earn cash back (the best part) with some of these money-savvy money hacks.

As some consumers have discovered, credit card processing fees can be evident when you make a purchase on your line of credit. The result of a recent lawsuit settlement between retailers, banks, and Visa and MasterCard, merchants are allowed to pass along such fees to their customers, according to Consumer World, which can be up to 4 percent.

There are ways to win the processing fee war and use credit card rewards to your advantage. Consider these for a few.

Buy gift cards at your local grocery store or gas station

To get discounts at your favorite retailers, buy gift cards through a grocery store using your credit card and save money in the process. “If you have a credit card that gives you something like 3-to-6 percent back on purchases made at the supermarket, you can buy gift cards at the supermarket — and therefore, in essence, save that 3 to 6 percent,” says Melanie Pinola from Lifehacker.

What are some of the best rewards cards for the job? According to Pinola, they include the American Express Blue Cash Preferred, which can offer up to 6 percent back at supermarkets (plus 3 percent cash back on up to $6,000 cash back on groceries spent annually, according to NerdWallet), AmEx Everyday (3 percent back at supermarket), or the grandfathered version of the same card, offering up to 5 percent back at supermarkets and pharmacies.

Get credit card rewards at unlikely retailers

Another grocery-related loophole, or “credit card hack,” is when you can use the same card to earn rewards at stores outside of the supermarket. What about using that card at Best Buy, Apple, or another retailer? “There are credit cards that offer varying amounts of rewards and cash back depending on where you choose to shop, rather than on what you actually buy,” says My Bank Tracker’s Simon Zhen, writing for U.S. News & World Report. “And since some retailers sell branded gift cards to other stores, you can be earning rewards on purchases that you won’t get if you used a credit card at those stores directly.”

Zhen adds, “A credit card that doles out 5 percent cash back on groceries may be used to purchase a Gap gift card at a supermarket. Effectively, the credit card user earns 5 percent cash back at Gap.”

Zero credit card interest, zero debt

You heard it right: you can pay off your credit card debt, interest free, with the services of a 0 percent interest credit card. “For this hack,” writes Libby Kane of Forbes, “you need either a respectable credit score in order to apply for a new card, or an existing credit card with zero interest.”

How does it work? For one, most credit cards charge an insane amount of interest — so if you’re in credit card debt, it’s not fun to get slapped with 18-20 percent per month and caught in a debt snowball. Avoiding the interest requires transferring your existing balance to a card that doesn’t charge any interest. “Essentially, you’re paying off the interest-bearing card using the new card, so your balance appears on a new bill, to pay down your debt without interest,” says Kane, who adds that this hacking maneuver could cost you about a 3 percent transfer fee — a small price to pay for resolving debt.

Free cash back, you say?

Zhen of My Bank Tracker writes in U.S. News & World Report that consumers with a prepaid American Express Bluebird account can earn cash back, with little spending involved, when they reload their accounts with a Vanilla Reload card, found at supermarkets, pharmacies and the like.

“Those who have credit cards that earn large amounts of cash back at these retailers can proceed to buy Vanilla Reload cards and refill their Bluebird accounts,” he said. “Then the Bluebird account can be used to pay for purchases that don’t earn cash back.” However, according to Zhen, don’t count on this hack to work 100 percent of the time; more retailers are catching on to this card scheme and have adopted a cash-only policy for the reload cards, preventing you from earning points on your card if you can’t use it towards the purchase.

Car rental insurance included

Most credit card reward programs involve earning and using points towards travel miles or retail products. One travel-related benefit most people are unaware of is that you can use your card to get car rental insurance. Most major credit card providers offer their own insurance policies at significantly lower prices than opting for the car rental agency’s insurance packages.

Card Hub conducted a survey last year that ranked Visa’s rental car insurance consumer approval rating at 87 percent. American Express and MasterCard also ranked highly, at 82 percent and 73 percent. When taking advantage of this credit card trick, make sure to first decline the rental agency’s insurance offer and use your credit card’s instead — you’ll need it to pay for the car rental.

It’s not wise to become the type of hacker we think of when we hear about the clandestine antics of groups like Anonymous. But with some of these sneaky — and legal — credit maneuvers, you can circumvent some loopholes to “hack” your credit card to a better, bigger, wealthier savings.

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