Not having a rewards credit card is a waste of a good credit score, but owning a rewards credit card without maximizing your points is just as wasteful.

There are plenty of ways to collect extra points, miles, and cash back without spending extra money. Follow these simple credit card tricks, and you could be adding a zero or two to your points balance in no time.

young woman holding credit card and smartphone and thinking with chin on fist

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Couple up your credit cards

Maybe your credit card offers extra points on travel spending, and the issuer has another card that offers extra points on groceries and gas. Consider getting a second card and switching them up depending on what you're purchasing in order to maximize rewards.

Transfer unused points

If you have a few thousand points sitting around in a rewards account you no longer use, you might be able to transfer those points to the rewards account you're currently using. Check your rewards program's point transfer policies and partnerships.

Put home improvements on the card

Planning on renovating the kitchen or adding a spare bedroom? Put those expenses on your rewards credit card, as long as you aren't charged a fee to do so.

Add an authorized user

This one requires a judgment call on your part. Adding someone as an authorized user makes you responsible for any debt they accumulate and fail to repay. It also means that any mistake you make, such as a late payment, will show up on their credit report, affecting their credit score. However, if you're sure you can trust each other, many credit cards give you extra bonus points -- usually around 5,000 -- for adding an authorized user who makes a purchase in the first few months. Plus, if that authorized user adds additional expenses to your card, the points they accumulate are added to your account.

Pay your mortgage or rent with a credit card

Services like RadPad and Plastiq let you pay your rent with a credit card. Your landlord doesn't even have to sign up; these websites send a rent check to your landlord on your behalf. Unless you find a promotion, it will cost you a 2%-3% transaction fee. This means you're paying 2 to 3 cents per $1, so you need to be getting back more than 2%-3% in rewards to profit. If you're trying to hit a minimum spend requirement to get the sign-up bonus on a credit card offer, the 2%-3% fee is almost always worth it.

Pay tuition with a credit card

If you're covering tuition for your kid, you might as well get a reward for all the money you're spending. Most colleges now allow you to pay tuition with a credit card, although many charge a fee. If you're lucky and the college you pay doesn't charge a fee for credit card transactions, charge away. Just make sure you have the funds to pay off your credit card immediately.

Pay your taxes with a credit card

As of 2018, the fee for paying any taxes you owe the federal government is 1.87% to 2%. That means this option is only worth it if you're getting more than 2% back, which can be in the form of high value points or a good cash-back credit card. If you're trying to meet a minimum spend requirement for a sign-up bonus, this option has lower fees than paying your rent online.

File a complaint

Did you recently experience an inconvenience with the airline or hotel chain you're trying to earn points for? Whether your flight was seriously delayed or your room was overbooked, complaining to the company will often result in them depositing a generous amount of miles or points into your account in exchange for your forgiveness.

Buy gift cards

Buying gift cards for places where you know you'll shop is an effective way to hit a minimum spend requirement. This can also be a good way to get extra cash back. For example, if your credit card offers 5% cash back on groceries, then buying restaurant or department stores gift cards at your local grocery store may let you get 5% cash back on purchases that aren't part of your bonus category.

Close your credit card -- and then reapply

Some credit cards only allow you to get a sign-up bonus once in a lifetime. However, other offers simply state that you cannot earn the sign-up bonus if you've already earned it once within the past 24 months. So, if you've had your rewards credit card for more than two years, you may be eligible to get the sign-up bonus again by closing it and reapplying. Just read the terms of the sign-up bonus carefully to make sure that you qualify. Also be aware that closing a credit account may ding your credit score by lowering your average account age.

Redeem your rewards wisely

Accumulating points quickly is only half of the process. In order to get the most out of your rewards, you have to redeem them wisely as well.

To choose what you want to redeem your points for, calculate how much you'd typically spend on your award redemption and divide that by the number of points it costs -- that's the value of each point, and you should aim for at least 1.5 cents. Redeeming points for products on a marketplace or for cash will typically get you the lowest value per point, while redeeming them for travel rewards like flights and hotels tends to get you the highest value.

Remember to weigh the costs of these methods with your potential rewards. After all, it's never worth it to spend more than you earn. It's also not worth charging more than you can afford to multiply your rewards, as credit card interest rates will surely cancel out any benefit. Whatever you do to earn points faster, don't let it get you into debt.

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