Postpaid usually means paying for something after you've already used or received it, rather than paying in advance.

With a postpaid cell phone plan, you use your phone all month, then receive a bill at the end showing how much you owe for the calls, texts, and data you used. This is the opposite of prepaid, where you pay money upfront and then use only what you've already paid for.

Many services work on a postpaid basis. Your family probably receives an electricity bill after using power all month, and restaurants bring the check after you've eaten your meal.

Postpaid can also describe mail or packages where the postage is arranged to be paid later through a special account, rather than requiring stamps upfront. You might see “postage will be paid by addressee” on business reply envelopes that companies want you to mail back to them. In that case, the company has set things up so the postal service charges them for the postage instead of you paying with a stamp.