Why use your own SMTP
Emails come from your domain.orders@yourshop.com instead of a shared address, which matters for a brand and for buyers deciding whether a delivery email is genuine.
Deliverability becomes yours. On a shared sender you inherit the reputation of everyone else using it. On your own domain, your sending history is your own, for better or worse.
It unlocks marketing. Email marketing campaigns can only be sent through your own SMTP server.
In exchange you own the setup: authenticating the domain, watching bounces, and keeping the reputation clean.
Requires a plan that includes SMTP.
What you need
1
A domain you control
Ideally the one your shop runs on. You need access to its DNS records.
2
An account with an email provider
See the comparison below. Most have a free tier that covers a small shop.
3
Your domain verified at that provider
Providers ask you to add DNS records, usually SPF and DKIM, sometimes DMARC. This proves you are allowed to send as your domain, and mail sent without it lands in spam.
4
The SMTP details entered in SellAuth
Your provider issues these once the domain is verified.
The settings
Choosing a provider
Any provider offering SMTP credentials works. These four cover most cases:
Not endorsements, and not an exhaustive list. What matters when comparing: does it give you SMTP credentials, does it support domain verification with SPF and DKIM, and what are the sending limits on the tier you would be paying for.
A free Gmail or Outlook mailbox is not a sending provider. Those accounts have low daily limits and are not intended for automated mail, so a shop using one tends to hit the limit partway through the day.
Keeping emails out of spam
Authenticate the domain properly. SPF and DKIM at minimum, added exactly as your provider specifies, and DMARC once those work. Warm up a new domain. A domain with no sending history that suddenly sends a thousand campaign emails matches the pattern spam filters look for. Let your delivery emails build a history first. Send marketing slowly. Campaigns have a throttle setting for this. See Email Marketing.Email templates
The same page holds the templates for every email your shop sends, which you can rewrite in full. Editing templates requires a plan that includes it, and the syntax, the variables each email receives and the shared layout are documented in Email Templates.Troubleshooting
Authentication failed. Username or password wrong, or the provider expects an API key rather than your account login. Connection refused or timing out. Wrong port, or the encryption setting does not match the port. Try 587 with TLS, or 465 with SSL. Emails send but land in spam. The domain is not authenticated, or Mail From is on a different domain than the one you verified. Some emails arrive and others do not. Usually a sending limit on your provider’s plan. Check its dashboard for rejected or queued mail. Nothing sends at all after configuring. Clear the settings to fall back to the SellAuth sender while you sort it out, so customers keep receiving their deliveries.Next steps
Email marketing
Campaigns and automations, which need SMTP configured.
Email templates
Rewriting the emails your shop sends.