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Credit question: What's the best credit card for cash back on gas purchases?

Answer: With gas prices inching upward, I've been getting this question a lot. There are really several credit cards that have pretty good cash back offers on gas purchases.

One that I particularly like is the Discover Open Road Card - $75 Restaurant.com Gift Certificate. You get 2 percent cash back on purchases at eligible gas stations and restaurants. This amount is capped at $250 per billing period, which isn't ideal, but once you reach the cap, you still get 1 percent on gas purchases. There's a zero percent introductory APR for 12 months and the go-to APR starts as low as 11.99 percent. If your first purchase is within six months of opening your account, you get a $75 Restaurant.com gift certificate. If you love dining out, that's a nice perk.

Many credit cards either exclude or offer a lower cash back percent on warehouse purchases. So if you buy gas at Costco, consider the True Earnings Card from Costco and American Express. You get 3 percent on gas purchases, up to $3,000 per year. After that, you get 1 percent. Plus, you get 3 percent for restaurants, 2 percent for travel, and 1 percent on just about everything else. The downside to this card is the 15.24 percent APR, although you do get a zero percent introductory APR for six months. If you don't carry a balance, it's a good card to consider for the gas savings.

If you know you'll put a lot of purchases on your credit card, then Blue Cash® from American Express® is another option. You only get 1 percent cash back on gas purchases for the first $6,500 you spend. But after that, you get 5 percent on eligible gas purchases.

At publishing time, Discover Open Road Card - $75 Restaurant.com Gift Certificate, True Earnings Card from Costco and American Express and Blue Cash® from American Express® are offered on Credit.com product pages and Credit.com is compensated if our users apply for and ultimately sign up for the card. However, this relationship does not result in ANY preferential editorial treatment.

Disclaimer: This content is not provided or commissioned by American Express. Opinions expressed here are author's alone, not those of American Express, and have not been reviewed, approved or otherwise endorsed by American Express. This site may be compensated through American Express Affiliate Program.

Image: L T Hunter