Who your emails come from

Emails to your subscribers use the name and address you connect in Settings → Email delivery. Replies go to that same address. Your sign-in email is separate. Connect an address on a domain you control, confirm mailbox ownership, add the domain authentication records, then choose Check verification. An address already registered with the email delivery provider must match your confirmed sign-in email or an address previously verified for your account.

Seamline checks current sender and domain verification before sending. Pending, revoked or unavailable verification holds sequence mail without spending delivery retries. Once verification succeeds, held sequence mail can resume automatically. Pause sending disables the sender and preserves the queue. Changing the sender requires verification again.

Sending depends on email-provider acceptance. A capture confirms a subscription, not email delivery. There is no Seamline fallback sender.

Writing new email sequences needs a paid plan. On the Collective plan, the "Built on Seamline" line is also removed from your hub.