Knowledge Base Connect a provider Connect Mailgun to RadarSend

Connect Mailgun to RadarSend

Mailgun is an email API that handles the actual delivery of your messages. This guide walks you through connecting your Mailgun account to RadarSend so you can send from your own verified domain.

Before you begin#

  • A Mailgun account (sign up at https://www.mailgun.com); a sending domain added and verified in Mailgun; access to your domain’s DNS; and a RadarSend account with admin access.
  • Note: Mailgun runs two separate regions, US and EU, each on a different API host. Check which region your Mailgun account and domain live in (shown in the Mailgun dashboard) — you’ll select it when you connect in Step 2.

Step 1 — Get your Mailgun credentials#

  • Sign in to Mailgun at https://app.mailgun.com.
  • Add and verify your sending domain. In the left-hand navigation, open Send → Sending → Domains, then click Add New Domain. A subdomain such as mg.yourdomain.com is recommended. Mailgun will list the DNS records to add — the SPF and DKIM (TXT) records are required, plus the tracking (CNAME) record for click and open tracking. Add these records at your DNS provider, then wait for Mailgun to verify the domain (DNS changes can take a few hours, occasionally up to 24–48 hours). You can click Verify DNS settings on the domain to check progress.
  • Get your API key. In the top-right corner, click your profile menu and choose API Security. On that page you’ll find your Mailgun API keys — click Add new key, give it a description, choose a role that can send, and create it. Copy the key immediately (Mailgun won’t show it again). You can also create a domain-scoped Sending API key under Send → Sending → Domain settings → Sending API keys.
  • Copy the API key and note your domain name (e.g. mg.yourdomain.com) — you’ll need both in the next step.

Step 2 — Add the sending service in RadarSend#

  1. In RadarSend, go to Settings → Sending → Sending services and click + Connect a service.
  2. In the wizard, on Choose your sending service, pick Mailgun, then click Continue.
  3. On Enter your Mailgun keys, fill in your API Key, your Sending Domain (e.g. mg.yourdomain.com), and choose the Region that matches your Mailgun account (US or EU). Then click Create.

RadarSend validates the fields and saves the service. It doesn’t live-test Mailgun at this point, so you’ll confirm that sending actually works in Step 4.

Step 3 — Turn on delivery, bounce & complaint tracking#

Set these up manually so RadarSend knows what happens to each message.

  1. Open the service: Settings → Sending → Sending services → your service.
  2. In the Webhook delivery section, you’ll see a webhook URL unique to your account (it looks like https://…/webhooks/mailgun/…). Copy it.
  3. In Mailgun, go to Send → Sending → Webhooks and add domain-level webhooks that point at that URL for Permanent Failure, Temporary Failure, Complained, and Delivered.
  4. Back in RadarSend, click Check to confirm the triggers are on.

Tip: Mailgun signs its webhooks. RadarSend verifies those signatures automatically using your API key, so there’s nothing extra to configure.

Step 4 — Confirm your sending address#

  1. Go to Settings → Sending → Senders and click + Add sender.
  2. Enter your Sending address (it must be on your Mailgun domain), then click Continue. Add a Display name and Reply-to, pick your email types, and click Continue.
  3. On Tracking & confirm, choose this service under Sending service (only shown if you have more than one), enter a test recipient, and click Send test.
  4. When the test is accepted, click Save sender.

If the test is rejected because your domain isn’t authenticated, RadarSend offers Authenticate {domain} (DKIM/SPF) and shows the DNS records to add. Tip: open the service and click Check verified domains to see which domains Mailgun has verified.

Common issues#

  • Domain still unverified / DNS not propagated. Mailgun can’t send until the domain shows as verified. Double-check the SPF, DKIM, and tracking records at your DNS provider and give them time to propagate (up to 24–48 hours).
  • Wrong region. If the Region you picked doesn’t match your Mailgun account, sends fail with “Domain not found” or 404-style errors. Open the service and switch Region between US and EU to match Mailgun.
  • From-address not on the Mailgun domain. Your sending address must be on the domain you verified in Mailgun (e.g. you@mg.yourdomain.com), not a generic Gmail or Outlook address.
  • API key lacking send permission. If you created a restricted key, make sure its role can send. When in doubt, generate a new key with sending access.
  • New account limits. New Mailgun accounts are often restricted until you add a payment method — do that in Mailgun if your sends are being blocked or capped.

Good to know#

  • Use a dedicated subdomain (e.g. mg.yourdomain.com) for sending. This keeps your root domain’s reputation separate and protected.