Mandrill is the transactional email service that we use at 18F. Note that the service is part of MailChimp, which we also use.

User setup

Invite the new user. Note they need to be an Admin to access Mandrill (unfortunately), per the Mailchimp documentation.

Accessing Mandrill

Moved from C2 documentation.

  1. Visit
  2. Click “Log In Through MailChimp”.
  3. Log in to MailChimp.
    1. If you have multiple options, select the “General Services Administration | 18F” account.

You should now be signed in to Mandrill with the shared account.

SMTP setup

This needs to be done for every sub-domain.

  1. Add a new Inbound Domain
    1. Click “View Setup Instructions” to get MX record info
    2. Add DNS records in Route 53 (domain needs to be delegated to us…if it isn’t, whomever controls the domain will need to do this)
      1. If domain is pointing to, add an A record as an alias to the same ELB that * is pointing to
      2. add the MX record
  2. Add new sending domain
  3. Set up SPF and DKIM records
    1. Click “View DKIM/SPF settings” and follow the instructions
    2. Enter TXT records in Route 53. Make sure to surround the values in quotes.
  4. At this point, verify that you have an A record, an MX record, and two TXT records for your domain
  5. Wait a little bit for the DNS records to propagate. Go get a coffee or something.
  6. In Sending Domains, click “Test DNS Settings”, and the DKIM and SPF should show up as verified.
  7. In Inbound Domains, click “Test DNS Settings”, and the MX records should be detected as valid.
  8. Verify the domain
    1. Create a new private
    2. Click the inbound domain and add new route, e.g. verify@, and set the Post To URL to be the URL
    3. On the sending domain page, trigger the Verify Domain, giving it that same email.
    4. “inspect” the RequestBin and get the verification link (refresh it, and search for verify-domain), removing all encoding, then visit it.

Still have questions?

Ask in Slack: #admins-mailchimp.