You've probably seen it.

Buy now, pay later.

Last holiday season, there were $16.6 billion in sales.

ABC 3340's Cynthia Gould explains how it works and how to keep your payments in check.

The offers are everywhere online.

Afterpay, Klarna, Affirm, and more.

Quick to get you approved, no hard credit check, and pay it off in four interest-free installments.

At least 100 million U.S. consumers have tried it at some point or another, and our survey finds that they really like it.

TransUnion's Liz Pagel says it can be a great tool, but remember this.

Downside is you really, really have to make sure you're not tempted to spend too much.

You have to make sure you can make every scheduled payment.

So when you click into that little offer, make sure you understand when the payments are gonna be due.

Make sure that you can not only make those payments, but also make the payments on everything else in your wallet.

Late payments can add up, and overdue balances turned over to debt collectors.

You need to keep a close track of when payments are due using autopay.

A cardrates.com survey found Americans carry an average of about $1,000 in buy now, pay later debt.

56% believe the trend is risky.

One in 10 have fallen behind on payments, and 23% feel they're encouraged to overspend.

It's most popular among the Gen Zers and millennials, but Pagel doesn't expect this trend to replace traditional credit cards anytime soon.

I think they're gonna coexist.

I think there's times when it makes sense to use a credit card, times when it makes sense to use buy now, pay later, and we're seeing consumers are using it all.

Pagel explains an added benefit, buy now, pay later could work to improve your credit score.

Coming soon in the next year or so, those positive payments, like when you're making your buy now, pay later payments on time, they'll be reflected on your credit report, and it'll be a way to start building credit.

So it's really, really exciting, especially for consumers that need a little boost there.

Now you are also do the same protections that you get with a credit card, the Consumer Financial Protection Bureau mandating things like refunds for returned products, help with merchant disputes, and bills which disclose the fees.

Cynthia Gould, ABC 3340 News.