Sending through an external service while displaying an address at a free mailbox provider can fail authentication alignment. The mailbox provider—not you—controls that domain's SPF and DMARC policy, and it may prohibit third parties from sending on its behalf.
An address on your own domain is also more recognisable and professional. It lets your organisation maintain the DNS records, DKIM keys and DMARC reporting needed for a durable sending identity.
Build the identity around a domain you control
- Use a stable From domain connected to your organisation.
- Include AuthSMTP in the domain's existing SPF policy.
- Enable AuthSMTP DKIM signing.
- Publish and monitor an appropriate DMARC policy.
- Keep the From and Reply-To identities understandable to recipients.
If you change domains, treat it as a reputation migration rather than a cosmetic edit. Authenticate the new identity, introduce it consistently and tell established recipients what is changing.
Use an address on your own domain and align it with SPF, DKIM and DMARC.
List every From domain currently used through AuthSMTP and confirm that your organisation controls its DNS and has authorised the complete sending path.
