How to Improve Email Deliverability

Deliverability is the ability of your emails to reach recipients' inboxes without being blocked or marked as spam. This guide covers everyday business mail: messages to clients, colleagues and suppliers.

How Sending Works on AtrioMail

• Outgoing mail is delivered through Amazon SES. Each sending domain is verified with Amazon and DKIM-signed for its own name, once its SES records are in DNS.
• This is shared infrastructure, not dedicated. Each AtrioMail customer account is its own tenant in Amazon SES, which lets sending be tracked account by account, but the sending infrastructure itself is shared.
• Bulk and cold email are not allowed: the Acceptable Use Policy bans unsolicited bulk mail and bought or rented lists, and every recipient must have opted in. Because all customers share the platform's sending reputation, we protect it for everyone.

If you need to send newsletters or marketing campaigns, use a dedicated email marketing service for those.

Step 1: Authenticate Your Domain

Receiving servers check three records to decide whether mail really comes from your domain:

• SPF lists the servers allowed to send mail for your domain.
• DKIM adds a digital signature that proves the message was not altered.
• DMARC tells receiving servers what to do when SPF or DKIM checks fail.

For every domain the panel generates SPF, DKIM and DMARC records ready to copy:

1. Go to Email Domains
2. Open your domain's DNS Setup dialog
3. Add every record listed there at your DNS host, including the Amazon SES verification records once they are generated
4. Click the refresh icon (circular arrows) on the domain's row to re-check the live records

On a connected Cloudflare or Namecheap account, AtrioMail can add the mail records for you, including the DKIM key. For any other DNS host, add them from the DNS Setup dialog.

Keep only one SPF record. If your domain already has one, edit it to include our value instead of adding a second.

You can check any domain with the DNS Checker in the control panel. It reports whether the MX, SPF, DKIM and DMARC records exist and are well-formed.

Step 2: Write Like a Person

Subject lines:

• ✅ Clear and descriptive
• ✅ Specific to the message
• ❌ Avoid ALL CAPS
• ❌ Avoid excessive punctuation!!!
• ❌ Avoid spam trigger words (FREE, URGENT, ACT NOW)

Message body:

• ✅ Professional formatting
• ✅ Proper spelling and grammar
• ✅ A sensible balance of text and images
• ❌ Avoid messages that are only a large image
• ❌ Avoid lots of links
• ❌ Avoid shortened URLs

Step 3: Send Carefully

• ✅ Check addresses before sending, and correct any that bounce
• ✅ Use a real name and a monitored address in the From line
• ✅ Ask regular contacts to add you to their address book
• ❌ Don't send the same message to a long list of people who did not ask for it
• ❌ Don't send attachments from unknown sources

Step 4: If Mail Lands in Spam

1. Check the domain's records in the DNS Setup dialog and click the refresh icon (circular arrows) on the domain's row
2. Check the domain with the DNS Checker
3. Review the message for spam triggers
4. Send a test to your own Gmail, Yahoo and Outlook addresses to see where it lands
5. Ask the recipient to mark the message as "Not Spam" and add you to their contacts

Useful outside tools:

• Mail-Tester: send a test message and see a spam score
• MXToolbox: check whether your domain is on a blocklist
• Google Postmaster Tools: see how Gmail views your domain

If Emails Bounce

• Check the recipient address for typos
• Check whether the recipient's mailbox is full
• Read the bounce message: it usually says why the mail was refused
• Remove addresses that no longer exist from your contacts

Need Help?

If mail keeps landing in spam after your records are in place, contact support through the live chat in the control panel. Include your domain, the recipient's provider, and an example message.