Improve outbound email deliverability for messages sent from Crisp, including replies, campaigns, and automated emails.

Deliverability depends on sender authentication, domain reputation, recipient engagement, bounce handling, and sending volume. Crisp provides tools such as custom email domains, custom SMTP, and email reputation pools, but good sending practices still matter.

In this article:

• Use Crisp deliverability tools → custom domains, SMTP, reputation pools, and dedicated IPs
• Warm up new sending infrastructure → how to ramp volume safely
• Prevent messages from going to spam → engagement, complaints, content, and technical checks
• Improve deliverability on any plan → practical adjustments even without advanced sending options

Use Crisp deliverability tools

By default, emails sent from Crisp use Crisp-managed sending infrastructure. If you want stronger brand alignment and more control over reputation, configure your own sending identity.

Set up a custom email domain

A Custom Email Domain lets Crisp send emails using your own domain instead of a default Crisp sending domain. This improves brand consistency and lets you build reputation under your own domain.

Use custom SMTP when needed

Custom SMTP lets you send Crisp emails through your own email provider or infrastructure. This is useful when your company already manages deliverability with a trusted provider.

Make sure your SMTP domain has valid SPF, DKIM, and DMARC records before sending volume through it.

Understand email reputation pools

Crisp uses email reputation pools to protect shared deliverability. Domains that send high-quality emails can use better reputation pools, while risky sending behavior can move a domain to lower-reputation pools.

Use a dedicated IP for higher control

A dedicated IP can help teams with significant sending volume control their own IP reputation. It also requires careful warmup. Sending too much too fast from a new IP can harm deliverability.

Warm up new sending infrastructure

New domains and IPs do not have established trust with mailbox providers. Warmup helps providers learn that your emails are legitimate and wanted.

Before warming up

Prepare your sending setup:

• Authenticate emails → configure SPF, DKIM, and DMARC correctly
• Use engaged recipients first → start with people who are likely to open and interact
• Clean your list → remove malformed addresses, unknown users, and unengaged recipients
• Monitor bounces and complaints → stop sending to segments that generate failures
• Create role mailboxes → monitor addresses such as abuse@ and postmaster@ for your domain

During warmup

Ramp volume gradually:

• Start low → begin with a limited number of engaged recipients
• Increase progressively → grow volume every few days rather than all at once
• Respect provider feedback → pause or reduce sending if bounces, complaints, or policy blocks rise
• Avoid forced volume → do not send extra emails just to hit a daily target
• Resume carefully → after a problem, hold volume steady before increasing again

Prevent messages from going to spam

Deliverability problems are easier to prevent than to repair. Watch the signals mailbox providers use to judge your sender reputation.

Watch engagement

Low open rates, low click-through rates, and low reply rates can indicate that recipients do not value the emails. Send fewer emails, segment better, and focus on content people expect.

Monitor complaints and bounces

Spam complaints and hard bounces damage reputation. Remove invalid addresses quickly and avoid sending to people who did not ask for the message.

Test message quality

Before sending a campaign or changing templates, test the message with a deliverability checker. Look for suspicious formatting, broken links, missing authentication, or content that looks spammy.

Audit technical records

DNS and authentication records can break after provider changes, migrations, or manual edits. Review SPF, DKIM, DMARC, tracking domains, and custom SMTP configuration regularly.

Useful external checks:

• Google Postmaster Tools → monitor Gmail reputation signals
• Microsoft SNDS or Postmaster tools → monitor Microsoft mailbox reputation where available
• Spamhaus and SpamCop → check blocklist signals
• DMARC analyzers → inspect SPF, DKIM, and DMARC alignment
• Mail Tester or similar tools → test individual messages before sending

Improve deliverability on any plan

Even without advanced sending options, you can improve deliverability by reducing unnecessary automated email and sending messages only when users expect them.

Chat transcripts can look repetitive because they are automatically sent at the end of conversations. If they generate low engagement or spam complaints, consider disabling automatic transcripts and sending them only on demand.

Good sending habits:

• Send expected emails → avoid unsolicited outreach from support infrastructure
• Reduce noisy automation → keep only emails that customers actually need
• Segment campaigns → send relevant messages to relevant contacts
• Keep lists clean → remove bounced, invalid, and inactive recipients
• Use your own domain → configure a custom email domain when you are ready to manage reputation

Updated on: 03/05/2026