Sending domain & deliverability

Sending email is easy. Getting it delivered is the actual work, and most of it happens once, at setup.

Verify your sending domain

Mail is sent through Resend. Add and verify your domain in the Resend dashboard, then set it as the sending address. The Newsletter tab shows live verification status, so you can confirm it's healthy without leaving Inkform.

Verification means publishing DNS records for:

Record	Answers
SPF	Which servers may send as your domain
DKIM	A signature proving the message wasn't altered and really came from you
DMARC	What receivers should do when SPF or DKIM fails

Until all three pass, expect mail to land in spam — or be rejected outright by Gmail and Outlook, which since 2024 require authentication from bulk senders.

Send from a subdomain you use only for newsletters, e.g. mail.example.com, not your main domain. If reputation is ever damaged, the blast radius is that subdomain instead of every transactional email your company sends.

One-click unsubscribe

Every campaign carries RFC 8058 headers (List-Unsubscribe and List-Unsubscribe-Post), so Gmail, Yahoo, and Outlook render a native Unsubscribe button next to the sender name. That's a requirement for bulk senders, not a nicety.

The unsubscribe link itself is signed and bound to one subscriber, so it can't be forged or replayed for someone else. A GET on it renders a confirmation page rather than unsubscribing immediately — that stops security scanners and link-prefetchers from silently unsubscribing people by following the link in their inbox.

Automatic suppression

Delivery events flow back from Resend and update each send:

Event	Effect
`delivered`	Recorded
`bounced`	Address suppressed — no future campaigns
`complained`	Address suppressed — no future campaigns

Suppression is permanent and automatic. You don't need to prune your list by hand, and you can't accidentally re-mail an address that already bounced.

Complaints are the number to watch. Keep them below roughly 0.1% — a few complaints per thousand sends is normal, sustained higher rates get you throttled or blocked.

Practical rules

Never buy or scrape a list. Beyond being illegal in most jurisdictions, purchased lists are full of spam traps — addresses that exist only to catch senders who didn't get consent. Hitting one can blocklist your domain outright.

Warm up gradually. A brand-new domain that suddenly sends 50,000 emails looks exactly like a compromised account. Start small and grow over weeks.

Send predictably. A list that hears from you weekly and then goes quiet for eight months will not remember signing up, and will mark you as spam when you return.

Make unsubscribing trivial. An easy unsubscribe is strictly better than a spam complaint: one removes an address, the other damages your domain's reputation for everyone.

When mail isn't arriving

Work through it in this order:

Check domain verification. SPF, DKIM, and DMARC all passing?
Check the Resend dashboard. It shows per-message delivery, bounces, and rejection reasons — that's the ground truth for what the receiving server said.
Check subscriber status. A subscriber who is pending never receives campaigns. That's the single most common "the newsletter isn't working" report, and it's usually working exactly as designed.
Check the confirmation email specifically. If people report never receiving it, confirm your sending domain is verified — unverified domains lose confirmation emails to spam, which silently caps every signup at pending.