Validate an address
Standardize a US address against USPS and check deliverability. Billed per call.
Validates and standardizes a US address against USPS without saving it.
Returns the standardized address plus deliverability intelligence: ZIP+4, carrier route, DPV deliverability, and whether the address is residential — which determines the residential surcharge most carriers apply.
**This endpoint is billed per call.** The amount charged is returned in the `billed` field. Cached results are billed the same as fresh lookups. Requests made with a sandbox API key are free and return a mocked result.
Address validation performed automatically inside `POST /v1/rates` is **not** billed — only direct calls to this endpoint are. `POST /v1/addresses/verify` is an alias of this endpoint and is billed identically.
Parameters
Request Body
street1
string
Required
Street address.
street2
string
Apartment, suite or unit. Include it — a unit number is part of the delivery point, so omitting it can change whether the address is deliverable.
city
string
Required
City name.
state
string
Required
Two-letter state code (e.g.
CA).zip
string
Required
5-digit ZIP or ZIP+4.
country
string
Defaults to
US. US addresses only today.Returns
200
Address validated
400
Invalid address payload.
NO_ORGANIZATION — the API key is not attached to an organization.
401
Authentication required
Related
addresses
validation
usps
POST/api/v1/addresses/validate