Deliverability

Deliverability is about making sure your emails actually reach your recipients' inboxes — not their spam folder, and not a bounce. Good deliverability requires verified sending domains, clean audience lists, and proper compliance practices.

Domain setup

Before you can send emails, you need to verify at least one sending domain. This proves to email providers (Gmail, Outlook, etc.) that you're authorized to send from that domain.

Adding a domain

1. Open Settings > Technical > Sending Domains.
2. Click Add domain and enter your domain name.
3. Owlat generates the DNS records you need to add.

Required DNS records

The exact records Owlat shows you depend on your sending provider — they're generated for you when you add the domain. Add each record exactly as displayed to your DNS provider (Cloudflare, Route 53, GoDaddy, etc.). The record types you may see are:

What records does my deployment generate?

Verification flow

1. Registering — your domain is being set up. DNS records are generated.
2. Pending — records are displayed. Add them to your DNS provider.
3. Click Verify — Owlat checks that your DNS records are in place and correctly configured.
4. Verified — all checks passed. You're ready to send.

Raising your DMARC policy

New domains start in monitor-only mode (p=none) so you can raise the policy gradually without risking legitimate mail. Once SPF and DKIM are aligned and verified, raise enforcement from the DMARC enforcement policy selector beneath the DMARC record in Settings > Technical > Sending Domains:

Changing the policy regenerates the _dmarc record shown above. Re-publish the updated record at your DNS provider and click Verify again so the new policy is confirmed. Only owners and admins can change the policy.

DKIM key rotation

Rotating your DKIM signing key periodically is good hygiene. When the domains.dkimRotation flag is on, Owlat flags keys that are due for rotation and, once an operator generates a new key, publishes the new public key as a DNS record for you to add. The new key only becomes active after its DNS record verifies, so there's no window where signatures break. On the built-in MTA, keys rotate on a safe overlap schedule (a new key is generated ahead of time and both keys remain valid during DNS propagation). You don't need to do anything beyond adding the new record when prompted.

Blocklist management

Owlat automatically blocks sends to email addresses that have caused problems — hard bounces, spam complaints, and other delivery failures. This protects your sender reputation.

How contacts get blocklisted

Contacts are automatically added to the blocklist when:

• An email bounces (hard bounce from the email provider)
• A recipient files a spam complaint

You can also manually add addresses to the blocklist from Settings > Technical > Email Blocklist.

How the blocklist affects sending

Blocked contacts are skipped during campaign sends — they won't receive any marketing emails. This happens automatically; you don't need to exclude them manually when selecting your audience.

Viewing the blocklist

Open Settings > Technical > Email Blocklist to see blocked addresses. For each entry you'll find:

• Email address — the blocked recipient
• Reason — why they were blocked (bounce, complaint, manual)
• Date — when they were added

Managing blocked addresses

In most cases, you should leave blocklist entries in place — they're there for a reason. However, if you know an address is valid and the block was a one-time issue (like a temporary mailbox-full bounce), you can remove the entry to allow re-sending.

Sending reputation

Owlat tracks your sending reputation automatically and surfaces it under Settings > Technical > Sending Reputation. You don't configure anything here — it's a monitoring view that updates as you send.

The dashboard has three monitoring cards plus a best-practices card:

• Sending limits — your current warm-up phase, today's daily send cap, how much of it you've used, and the individual sending IPs the built-in MTA is warming. Warm-up phases are shown as Warming Up (capacity ramping), Paused, or Fully Warmed. The MTA raises your daily capacity automatically based on bounce and deferral signals; new IPs typically take around 30 days to fully warm. This card also surfaces your account health: if your bounce or complaint rates cross critical thresholds, your account status moves from clean to warned, suspended, or banned, and a banner explains the restriction.
• Account reputation — your rolling 30-day bounce rate, complaint rate, delivery rate, total sent, and an overall risk level. Targets are below 2% bounce and below 0.1% complaints.
• Domain reputation — the same bounce/complaint/risk breakdown per sending domain, joined with each domain's verification status, so you can spot which domain is dragging down delivery.
• How to Improve — best-practice tips for keeping your reputation healthy.

Unsubscribe and preferences

Owlat includes built-in unsubscribe and preference management to keep you compliant:

• One-click unsubscribe — every marketing email includes an unsubscribe mechanism that meets CAN-SPAM and GDPR requirements
• Preference center — contacts can manage their per-topic subscription preferences, choosing which topics they want to remain subscribed to

Preference center

The preference center is a hosted page where contacts can manage their own subscriptions. It shows all topics the contact belongs to and lets them opt out of individual topics without unsubscribing from everything.

• Links to the preference center are automatically included in email footers
• Access is secured with HMAC-signed tokens — contacts can only view and modify their own preferences
• Available at the /preferences public endpoint

These work automatically for all marketing campaigns. You don't need to set anything up.

Compliance essentials

Email laws vary by region, but the core principles are universal:

CAN-SPAM (United States)

• Include a valid physical mailing address
• Provide a clear unsubscribe mechanism (handled automatically by Owlat)
• Honor unsubscribe requests promptly
• Don't use misleading subject lines or sender information

GDPR (European Union)

• Obtain explicit consent before sending marketing emails
• Provide easy opt-out mechanisms
• Respect data subject access and deletion requests
• Document your consent collection process

General best practices

• Only send to people who have opted in
• Make it easy to unsubscribe
• Set clear expectations about what subscribers will receive
• Process unsubscribes and complaints quickly

Sending hygiene checklist

Good deliverability is an ongoing practice, not a one-time setup:

• Verify your domain before your first send
• Start small — warm up a new domain by sending smaller batches first and gradually increasing volume. The built-in MTA handles this for you and ramps your daily cap automatically; track progress under Sending reputation
• Keep bounce rates low — remove invalid addresses after they bounce
• Keep complaint rates below 0.1% — high complaints signal to email providers that your emails aren't wanted
• Clean your lists regularly — remove contacts who haven't engaged in 6+ months
• Use double opt-in on public signup forms to verify email ownership
• Monitor your metrics — watch for sudden changes in open rates, bounce rates, or complaint rates

Next steps

• Campaigns & Reporting — monitor your campaign performance
• Topics — manage subscription and double opt-in
• Contacts — maintain a clean audience
• Forms — collect contacts with proper opt-in