> how do you then even know what ZIP code to use

There has always (since the late 90s) been a free look up webpage:

https://tools.usps.com/zip-code-lookup.htm

The data used to be available on CDROM (back in the 90s) but moved to an API in the early 2000s. Until August 2026, you used to be able to look up addresses for free.

To get the biggest discount on postage (one place I worked at mailed about 3k envelopes per month) you have ZIP+4, to pre-sort the mail and print a bunch of stuff on that barcode [0]. Next time you get an envelope, look at the barcode on the bottom.

https://en.wikipedia.org/wiki/Intelligent_Mail_barcode

0 - doing it that way saved about $450/month versus not doing any of their work for them.

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10111001 an hour ago | parent [-]

> The data used to be available on CDROM (back in the 90s) but moved to an API in the early 2000s. Until August 2026, you used to be able to look up addresses for free.

What was the reason for the 2026 change to make it non-free? Some "government should be run like a business" (and therefore charge for services) BS, or was there some kind of abuse or privacy issues they were trying to limit?

	▲	dn3500 4 minutes ago \| parent \| next [-]
		My university used to get copies of the CDs in the 1990s. I think they came out quarterly. You had to pay for the CDs, but the data was free. We bought one copy and put it on a server for everyone to use. All governments provide some services for "free" and charge for others. Sometimes it makes sense, other times it really is BS.
	▲	peezd an hour ago \| parent \| prev [-]
		Mostly as a commercial shift under the new board of governors that are concerned on financials (except when it comes to throwing away new efficient mail sorting machines ahead of an election). They spun it as supporting the new RestAPI based system they put in place, it does have more efficient rate limiting, and some controls like Mailer ID verification (able to tie who makes a request for a label to that actual label, etc.) that are supposed to help with fraud.