Mailgun - Nitrosend

Use your Mailgun account as the sending provider for Nitrosend campaigns, flows, and transactional email. See Email providers for how BYO sending works, plan requirements, and status semantics.

What you need

Your Mailgun API key (private API key from the Mailgun dashboard).
Your Mailgun sending domain (the domain you send from in Mailgun, e.g. mail.yourdomain.com).

Nitrosend connects to Mailgun's US API endpoint and validates the key by listing your Mailgun domains when it tests the connection.

Warning

EU-hosted Mailgun accounts are not currently supported — connections use Mailgun's US endpoint.

Connect from the dashboard

Go to Integrations in Nitrosend.
Choose Mailgun.
Enter the API key and sending domain, then save. Nitrosend tests the connection as part of saving a new integration.

Connect via MCP

Info

In the MCP tool, the region argument carries the Mailgun sending domain — not a geographic region.

{
  "operation": "configure",
  "provider": "mailgun",
  "api_key": "<MAILGUN_API_KEY>",
  "region": "mail.yourdomain.com"
}

Warning

The MCP call stores the credentials without testing them. {"operation": "status"} reports stored configuration only — to actually test the credentials, run Test connection from the Mailgun integration page in the dashboard, or call POST /v1/my/integrations/{id}/test via the REST API.

Making it the active provider

If this is your first BYO provider, it becomes the brand's active email provider automatically. If you already had another provider connected, open the integration's page and choose Set as primary to switch sending to it.

Sending domains

After connecting, add your sending domain from Domains (or nitro_manage_domains). The DNS records returned come from Mailgun's domain verification.

Troubleshooting

Connection test fails — confirm you're using the private API key, that the key's account can list domains, and that your Mailgun account is US-hosted.
Rotated your key? Re-entering credentials resets this integration's verified domains to pending — re-verify them from Domains.