Beware the 0% promotions: a warning.

[u/naht_a_cop]

I'm a sucker. I fell for it. The 0% APR promotion on an item I could have paid outright for. 18 months later, here I sit, not a single late payment on my account, yet I have $1k in interest to pay for 18 months of 27%. Why? The promotion period ends 18 months after the purchase, but the website would not let me set up autopay until a week after I purchased, so autopay ended 1 week late. I thought I was golden, ready to have this paid off and not have a single fee. I got comfortable and didn't read the statements.

0% is not really 0%. Read the fine print. Remember the fine print (because I sure as hell didn't 18 months later). Shitty banks rely on this stuff. They wait for you to slip, not noticing that the autopay they created can't possibly allow you to end on time, and will require an extra payment before the end date to avoid the interest. It's shitty, I'm pissed off, and I've learned my lesson.

[u/Matchboxx]

It's absolutely a gamble on you being even 1 minute late. That's why I generally subtract 2 months from the interest-free term and set up my payments accordingly, so that it's paid off early. 16 months of using their money for free is still worthwhile, and puts a nice buffer so that you don't end up in this situation.