That $80 pair of sneakers breaks into four easy payments of $20.
No interest, no credit check, just a few taps at checkout.
But that convenience has a catch that's been quietly growing alongside the service's popularity.
Buy now, pay later services like Affirm, Klarna, and Afterpay are now baked into checkout pages at nearly every major retailer.
A 2023 report from the Consumer Financial Protection Bureau found that roughly 20% of BNPL users had overdrafted a bank account to make a payment, and about 10% had been charged a late fee.
Those fees tend to run $5 to $10 per missed installment, and on a small purchase, that can wipe out the entire "no interest" benefit.
Stores and lenders love this model because it nudges shoppers to spend more.
Research from Harvard Business School found that BNPL customers spend 10% to 40% more per transaction and are more likely to buy on impulse.
When a $60 purchase becomes "just four payments of $15," your brain stops doing the math on whether you actually need it.
Multiple apps, multiple paydays, and suddenly three or four automatic payments are hitting your account in the same week.
Miss several, and some services report you to credit bureaus or hand your debt to a collection agency.
Unlike a credit card, many BNPL plans don't show up on your credit report when you pay on time, so you get none of the score-building upside while carrying all the downside.
If you're using these services, a few habits help.
Track every active plan in one place, whether that's a notes app or a spreadsheet.
Never let a payment draft from an account with a tight balance, and set a calendar reminder a day early.
If you're juggling more than two plans at once, that's a signal to pause new purchases until the balances clear.
The feature isn't evil, and plenty of people use it responsibly to smooth out cash flow.
But "four easy payments" is marketing, not a budget strategy.
Final Thoughts
Treat it like any other debt: know the total, know the due dates, and don't sign up just because the button is right there.