C938 UNITED STATES POST OFFICE

Facility details

FIRMS code

C938

Name

UNITED STATES POST OFFICE

Address

BALTIMORE/WASHINGTON INT'L AIRPORT

BALTIMORE, MD 21240

Status

Active (A)

Facility type

Importer's premises (06)

CBP port

Baltimore, MD (1303)

CBP region

1

Last changed

2026-10-23

Data as of

2026-10-23

Pre-filing validation

Validate C938 before you file

Check C938 against the port and use on your filing before ACE does: list, status, port (ACE 164) and facility type.

curl https://api.firmsapi.com/v1/validate \
  -H "x-api-key: $FIRMSAPI_KEY" -H "content-type: application/json" \
  -d '{"code":"C938","port":"1303","use":"location_of_goods"}'