The USPS address API is now paid. Here are your options.

Prices checked October 2, 2026 from each vendor's public pricing page. Prices change; confirm on the vendor's site before you buy.

What changed

Starting August 1, 2026, the USPS Addresses API v3 (version 3.3.1, "Enhanced") requires a signed license agreement and a funded Enterprise Payment Account (EPA).
The free version is being eliminated. In a filing with the Postal Regulatory Commission, USPS said about 70% of its ~8,000 Addresses API users used it for non-mailing purposes.
Fees are charged at the start of each month for the previous month's usage and debited from the EPA.

What USPS charges now

Requests in the month	Price
1 – 2,000	$10 flat fee
2,001 – 10,000	$4.50 per 1,000
10,001 – 50,000	$4.25 per 1,000
Over 50,000	$4.00 per 1,000

The whole month is billed at a single tier based on your total, and tiers 2–4 are charged per 1,000 "or fraction thereof". Example (our arithmetic): 9,500 requests = 10 × $4.50 = $45. 20,000 requests = 20 × $4.25 = $85.

What else comes with the license

The USPS Addressing API License (April 2026 version) limits what you can do:

Use is limited to "Updating Addresses and Attributes."
Each end user of a third-party app must be a licensee with its own credentials (§2.2.2).
No reselling or sublicensing the services or credentials (§3.3).
No building a service that competes with USPS (§3.12, §4.4).
Every request must go to USPS; you can't answer from your own cache (§4.3).
Attributes may be passed on only for internal use for USPS mail delivery (§5.1).

Older USPS Web Tools docs described the address APIs as for "USPS SHIPPING OR MAILING SERVICES ONLY." If you used the free API for form validation, sign-up checks or CRM cleanup, read the license carefully before signing.

How to sign up (if you stay with USPS)

Create or log in to a USPS Business Portal (COP) account.
Create and fund an Enterprise Payment Account (trust funding, ACH debit or credit card).
Accept the updated terms in the Business Portal.
Request an Addresses API license under My Account › API Licenses.
Sign the order form and license by DocuSign.
Wait for USPS to countersign, then link your API credentials to the license.

Rate limits: the USPS developer portal historically allowed 60 calls per hour per API by default. The current page no longer states a number, so we could not confirm the limit under the new license.

Alternatives with published prices

Monthly cost for a few common US volumes, using each vendor's published plan (our arithmetic; taxes not included). Try your own number in the cost calculator.

Option	1,000/mo	5,000/mo	10,000/mo	50,000/mo
USPS	$10	$22.50	$45	$212.50
Google (Pro)	$0 (free cap)	$0 (free cap)	$85	$765
Smarty (monthly plan)	$17	$50	$88	$258
PostGrid (Standard $18 plan)	$18	$78	$178	$978*
Lob	$25	$125	$250	$450
EasyPost (standalone)	$20	$100	$200	$1,000
Shippo	$20	$100	$200	$1,000
Loqate ($100 pack rate, 6¢)	$60	$300	$600	$3,000

*PostGrid publishes larger plans (10,000/month with $0.01 extra; 50,000/month with $0.005 extra) but their monthly prices were not shown on the page we checked, so the larger volumes here use the $18 plan and would likely be lower on a bigger plan. EasyPost verification is free with each label you buy. Loqate's rate drops to 4.1¢ with the $1,000 pack. Melissa is left out because its credit math is ambiguous; see Melissa.

Other options people are using

Only need a map location? A geocoder such as Geocodio (2,500 free lookups/day) or Geoapify (3,000 credits/day) may be enough. They do not check postal deliverability.
Shipping anyway? EasyPost includes verification free with labels.
Need CASS-processed lists for postage discounts? USPS markets the new API as removing the need for your own CASS certification. Licensing your own CASS software or USPS AMS data means separate USPS licenses and fees, which we have not priced.