Whole Foods Market + Amazon
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Amazon took ownership this week of Whole Foods with a newsworthy bang by slashing prices on many products. The pricey supermarket chain offered discounts of up to 43 percent on everything from organic avocados to responsibly-farmed Tilapia.

For price-conscious consumers, this is a big win.

But you can save even more by employing another smart shopping strategy: Use a credit card that offers cash back on groceries. Some of the more generous rewards cards rebate up to 6 percent on supermarket spending.

Credit cards that can save you money

Don’t make the mistake of relying solely on sales and coupons to save money. If you do a lot of grocery shopping, a rewards credit card should be part of your savings arsenal.

The Blue Cash Preferred Card from American Express is a prime example. Card owners earn a whopping 6 percent cash back on U.S. supermarket purchases of up to $6,000 per year (then 1 percent). Plus, new cardholders earn a $200 statement credit after spending $1,000 in purchases within the first three months of card ownership. The card carries a $95 annual fee.

If you hit that minimum spending requirement at the supermarket alone, you will earn $260 — for doing something you would have done anyway. And if you spend $100 at the supermarket per week, you’ll earn more than $300 per year. That’s three weeks of free groceries.

The Bank of America Cash Rewards Credit Card is another option. This long-time favorite of people who want a low-maintenance card — there is no annual fee — comes with considerable perks.

In this case, shoppers earn 2 percent back at grocery stores and wholesale club purchases up to $2,500 in combined spending per quarter. On top of that, Bank of America customers can get a 10 percent customer bonus when cash back rewards are redeemed into a Bank of America checking or savings account.

This card also comes with a $150 sign-up bonus; all you have to do is spend $500 within 90 days of opening your card.

More than just groceries

If you want to earn cash back on more than just your supermarket spending, you might consider a cash-back card that offers higher rewards on certain rotating categories throughout the year. The Chase Freedom card is a top pick.

Cardholders will earn 5 percent cash back on up to $1,500 in combined purchases per quarter on rotating categories that include groceries, restaurants, gas, movie theaters and even holiday shopping. Users still earn 1 percent on all other purchases.

Chase makes it easy to find out which category is good for the 5 percent offer, so you can plan your spending accordingly. For example, the current bonus categories (through September) are restaurants and movie theaters.

Remember, a good cash-back credit card is just another savings tool — like great deals (thank you, Amazon) and coupons — provided you sidestep interest rates and pay off your balance every month.

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