Credit cards can help you build your credit score, which can qualify you for a better loan rate when you buy a house or a car one day. And they can earn you cash back, so, as a strategic spender, you can use different rewards cards for different types of purchases and maximize savings. But the benefits don't stop there: Credit cards offer a wide range of perks, many of which are underutilized — in part because lots of people don't know they exist. In a recent WalletHub survey, less than half of the respondents were familiar with secondary credit card benefits, or benefits that might not be a card's main feature but, when taken advantage of, can still save you time and money. Here are seven of the top credit card perks you may not know about.

Price protection

If you buy an item on your credit card and then its price drops within a set time frame, usually a month or two, you can get refunded the difference between what you paid and what you would have paid if you'd waited. You just have to submit a claim form. In the Wallethub survey, one out of four respondents said they wanted a card that offered price protection, making it the most popular of any secondary benefit. Fewer credit card issuers are now offer it, according to U.S. News, but it remains available to many. Citi cardholders, for instance, can receive a reimbursement up to $200 within 60 days of the initial purchase of select items, while Discover will reimburse its cardholders up to $500 per item within 90 days.

Lounge access

Many elite travel cards provide complimentary access to hotel and airport lounges throughout the world. Why buy marked-up cocktails in the airport terminal as you wait for your flight when you can get them for free, accompanied by a meal designed by a celebrity chef? The Chase Sapphire Reserve, CNBC Make It's runner-up for the best travel card, offers airport lounge access through Priority Pass Select. The American Express Platinum, meanwhile, our top luxury card, provides free admission to Centurion lounges, many of which are equipped with amenities such as shower rooms and wine-tasting stations.

Free hotel stays

This is a common perk of hotel-branded cards. The World of Hyatt card, for example, offers one free night at a Hyatt hotel or resort once a year after your first year, plus an additional free night if you spend $15,000 on the card in a year. General travel cards often offer it, too, through programs such as Fine Hotels & Resorts by American Express. With this benefit, you can also receive room upgrades, complimentary breakfast, late-check out and, on occasion, access to unique property amenities like spas.

Bonuses

Sign-up bonus are hardly a secret: They're the the primary motivation for a quarter of the people who get new cards. The Citi ThankYou Premier offers 60,000 points for cardholders who spend $4,000 within the first three months. That's $750 towards a flight, since points are worth 1.25 cents each when redeemed on airfare, which makes it the best bonus of any travel credit card. If you transfer points to a partner rewards program, you could potentially get even more value. Business cards bonuses can be even higher: The Chase Ink Business Preferred offers 80,000 points. When redeemed towards travel, that's worth $1,000. What's less well-known is that some cards offer additional bonuses for users who meet certain spending requirements. Take the Barclays Arrival Premier World Elite Mastercard, for example. Cardholders who spend $15,000 on purchases in a year receive 15,000 extra miles. Spend $10,000 more, and you get an extra 10,000 miles.

Pre-sale tickets and VIP packages

If you love going to concerts, games and other events — and don't enjoy getting scammed — some credit cards let you get tickets safely and before they're available to the general public. Select Citi cards offer Citi Private Pass, which cardholders can use to purchase pre-sale tickets and VIP packages, and American Express partners with Ticketmaster to provide a similar service for its cardholders.

Insurance

Travel credit cards offer various types of coverage. For instance, the Chase Sapphire Reserve offers a fairly comprehensive package, including trip accident insurance, rental car insurance, lost or delayed luggage insurance, trip cancellation or delay insurance, and even emergency medical and dental insurance. Meanwhile, some cards, like the U.S. Bank Visa Platinum, offer cell phone damage protection. In many cases, if you want to take advantage of insurance perks, you have to be aware they're offered. U.S. Bank will only cover your broken iPhone screen if you use their card to pay your phone bill. And a rental car salesman working for commission and trying to get you to buy a policy through him may not mention the fact that your credit card actually already offers a damage waiver when he's warning you about the recent hail storms in the area.

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