USGM Public API

Programmatic access to your US Global Mail mailbox — mail items, scans, shipments, folders, and addresses.

The USGM Public API lets you manage a US Global Mail mailbox from your own code: list and organize scanned mail, request scans, manage folders, view shipments, and manage shipping and deposit addresses. It’s a REST API over HTTPS with predictable, resource-oriented URLs, JSON request and response bodies, and standard HTTP status codes.

Base URL

All requests go to the gateway over HTTPS. The path always includes the API version (/v1).

EnvironmentBase URLKeys
Productionhttps://api.usglobalmail.comusgmk_live_…
Sandboxhttps://api-sandbox.usglobalmail.comusgmk_test_…
$curl https://api.usglobalmail.com/v1/mails \
> -H "Authorization: Bearer usgmk_live_…"

The sandbox is a full copy of the API that never touches live mail. Develop against it with a usgmk_test_… key, then swap in a usgmk_live_… key and the production base URL to go live.

Conventions

  • Authentication — every request needs your API key as a bearer token. See Authentication.
  • JSON — request and response bodies are JSON; timestamps are ISO-8601 (2026-07-13T14:32:00Z).
  • Ids — resource ids are strings. Mail items and folders use numeric strings; everything else uses UUIDs.
  • Pagination — list endpoints return { data, next_cursor }. See Pagination.
  • Errors — non-2xx responses are RFC 9457 application/problem+json. See Errors.
  • Rate limits — requests are throttled at the edge, keyed by API key. See Rate limits.
  • Status — live uptime and incidents are at status.usglobalmail.com. See System status.