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Add or verify a Mailtrap sending domain, troubleshoot DNS propagation, publish SPF/DKIM/DMARC records, and complete compliance.
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Based on SOC occupation classification
Manage Mailtrap contacts, lists, segments, custom fields, imports, CRM syncs, and campaign audiences through the UI or API.
Configure or troubleshoot Mailtrap live email sending with Email API, SMTP, transactional streams, bulk streams, or batches.
Find, compare, adapt, and design bounded AI-agent feedback loops with explicit checks, stop rules, guardrails, and handoffs.
| name | mailtrap-setting-up-sending-domain |
| description | Add or verify a Mailtrap sending domain, troubleshoot DNS propagation, publish SPF/DKIM/DMARC records, and complete compliance. |
| risk | safe |
| source | community |
| date_added | 2026-06-19 |
You must add and verify a domain you control before live sending. Mailtrap shows every DNS record required for that domain in the UI: add the complete set as given (do not cherry-pick). After DNS verifies, complete the compliance step if requested.
Subdomain vs root: add the exact hostname you will use in the From address. If you send from notifications.mycompany.com, add that subdomain as the sending domain—not only mycompany.com, unless you truly send from the root domain.
For step-by-step clicks at common hosts, open the matching guide on Sending domain setup (Cloudflare, Route 53, etc.) and follow it alongside the live UI values.
Related skills: mailtrap-sending-emails (after domain is ready).
mailtrap-testing-with-sandbox)The Sending Domains API calls below need Authorization: Bearer $MAILTRAP_API_TOKEN and an $MAILTRAP_ACCOUNT_ID in the path. Resolve $MAILTRAP_ACCOUNT_ID from GET https://mailtrap.io/api/accounts, and store tokens in environment variables or a secrets manager.
Prefer this path when building scripts or AI-assisted automation:
GET https://mailtrap.io/api/accounts/$MAILTRAP_ACCOUNT_ID/sending_domains — lists domainsGET https://mailtrap.io/api/accounts/$MAILTRAP_ACCOUNT_ID/sending_domains/{sending_domain_id} — returns dns_records (each with type, name, value, and verification status) and dns_verified. Poll after you publish DNS.POST https://mailtrap.io/api/accounts/$MAILTRAP_ACCOUNT_ID/sending_domains with domain_name when your flow provisions domains programmatically.Human fallback: Sending Domains > Add domain > copy values into the registrar UI > Verify when API automation is not available.
dig, nslookup, or an online DNS lookup to confirm each record is visible publicly before clicking Verify again.Product walkthrough: Sending domain setup.
Mailtrap publishes click-path guides for common providers. Open the page that matches the user's DNS host and follow it together with the live UI records:
If the user's provider is not listed, the same rule applies: copy every record from Mailtrap into the DNS zone that serves the From domain.
If your DNS provider proxies records (orange-cloud on Cloudflare, similar CDN/proxy modes elsewhere), verification-related records must be DNS-only (grey cloud / non-proxied) unless Mailtrap documentation explicitly allows proxying—proxied CNAMEs and similar often break SPF/DKIM verification. The same constraint applies to any host that fronts DNS with a proxy.