The Only 3 Credit Cards You Really Need

You don't need a wallet full of credit cards to win the rewards game. In fact, Americans only carry about 3.9 cards on average, according to Experian -- and you can do a lot with even fewer.

Here's a basic three-card strategy that will get you maximum rewards while also protecting your credit score.

1. Keep your oldest credit card

Even if it's not flashy, your oldest card might be the most important one to hang on to.

That's because the age of your credit accounts plays a big role in your credit score. Canceling a long credit line history will almost certainly ding your score.

So unless that card is charging you a hefty annual fee, keep it open. Maybe tuck it in a drawer and use it for a small recurring subscription to keep it active.

2. Get a card that matches your biggest spending category

If you're spending hundreds (or thousands) of dollars each month in a particular category, this is a big opportunity to boost your cash back, points, or miles.

I spend about $500 a month at Trader Joe's. So having a solid grocery rewards card is huge for me.

The key is matching the right card to your actual spending. Maybe you want a card that earns points for dining out. Perhaps you'd prefer a card that earns cash back on gas and groceries, or you're ready to plan a getaway and want to redeem a free flight with travel rewards points. No matter what, the right card for you is out there.

Attention Costco lovers! If you shop the warehouse a lot or at Costco.com, check out these best credit cards for Costco which generally earn 2% to 3% back on all purchases.

3. Use a "catch-all" card for everything else

Not every purchase fits into a neat rewards category. That's where an everyday general purpose card comes in handy.

A great goal here is to get at least 2% back on your everyday spending.

Look for cards that offer:

• 2% cash back on all purchases (or the equivalent in points value)
• A low or no annual fee
• Simple reward redemption options

Explore top cash back cards here and start earning more on every swipe.

How many cards is too much?

There's no "perfect" number of credit cards that everyone should have. The best approach is staying within your comfort level.

But one thing's for sure: If you're only using one basic card right now -- or worse, a debit card, eek! -- you owe it to yourself to explore better card options.

A simple switch could put hundreds of extra dollars in your pocket each year.