> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.usglobalmail.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.usglobalmail.com/_mcp/server.

# Gateway timeout

Returned as `application/problem+json` with `code` `gateway_timeout` and HTTP status `504`.

An upstream service took too long to respond.

## Common causes

* A slow or unresponsive downstream dependency.

## How to resolve

* Retry with backoff.
* If it persists, contact support with the `request_id`.

## Check system status

A `504` is a server-side failure, so it may reflect a known incident rather than a problem with your
request. Check the [System status page](/guides/core-concepts/system-status) — if there's an open
incident affecting the USGM API or USGM Core, the issue is on our side, so wait for it to resolve. If
everything is operational and the error persists, contact support with your `request_id`.

## Example

```json
{
  "type": "https://docs.usglobalmail.com/api/problems/gateway_timeout",
  "title": "An upstream service timed out.",
  "status": 504,
  "code": "gateway_timeout",
  "request_id": "req_8f3c2a1b9d",
  "instance": "/v1/mails"
}
```

> **Note**
>
> This error is typically transient — safe to retry with exponential backoff.