Sending Domain Setup
A sending domain authenticates your outgoing emails with DKIM and DMARC, ensuring they are delivered reliably and not marked as spam. This requires a CNAME record for domain verification, a TXT record for DKIM signing, and a TXT record for DMARC policy. To create a sending domain in Lettr:- Select Domains in the navigation panel
- Select Sending Domains
- Click Create Sending Domain
- Enter your desired sending subdomain (e.g.
mailing.company.com) - Click Create Domain
Configure Netlify DNS
Netlify DNS is managed at the team level, not per site. Log in to the Netlify dashboard and select DNS from the left sidebar in your team dashboard. Select the domain you want to configure to open its DNS records panel.Domain registered with a different registrar?
Domain registered with a different registrar?
If you registered your domain elsewhere but want to manage DNS on Netlify, you must first add the domain to Netlify
DNS and then update the nameservers at your registrar to Netlify’s nameservers. Your domain’s assigned
nameservers are displayed in the Name servers panel on the domain’s DNS page — they follow the format
dns1.p0X.nsone.net through dns4.p0X.nsone.net, where the partition number is unique to your domain.Add CNAME Record
The CNAME record verifies domain ownership with Lettr’s email infrastructure. Copy the CNAME values from Lettr to Netlify:- Click Add new record in the DNS records section.
- Set Type to CNAME.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix). For example, paste only
mailing. - Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
mailing, not mailing.company.com).Add TXT Record (DKIM)
The DKIM record adds a cryptographic signature to your outgoing emails, allowing recipients to verify they were sent by an authorized sender. Copy the TXT values from Lettr to Netlify:- Click Add new record in the DNS records section.
- Set Type to TXT.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix). For example, paste only
scph0126._domainkey.mailing. - Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
scph0126._domainkey.mailing, not scph0126._domainkey.mailing.company.com).Add TXT Record (DMARC)
The DMARC record tells receiving mail servers how to handle emails that fail authentication checks, protecting your domain from spoofing. Copy the TXT values from Lettr to Netlify:- Click Add new record in the DNS records section.
- Set Type to TXT.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix). For example, paste only
_dmarc.mailing. - Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
_dmarc.mailing, not _dmarc.mailing.company.com).Verify Your Sending Domain
After adding all three DNS records, go back to Lettr and click Verify DNS Records. DNS propagation can take up to 24–48 hours, though it typically completes within a few hours on Netlify.Inbound Domain Setup
An inbound domain allows Lettr to receive emails on your behalf. This requires three MX records that direct incoming mail to Lettr’s mail servers.Add Inbound Domain to Lettr
To create an Inbound domain in Lettr:- Select Domains in the navigation panel
- Select Inbound Domains
- Click Create Inbound Domain
- Enter your desired inbound subdomain (e.g.
inbound.company.com) - Click Create Domain.
Add MX Records
MX records tell other mail servers where to deliver emails addressed to your domain. Copy the MX values from Lettr to Netlify:- Click Add new record in the DNS records section.
- Set Type to MX.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix). For example, paste only
inbound. - Copy the first Required MX Record value (e.g.
rx1.sparkpostmail.com) from Lettr and paste it into the Value field. - Set Priority to
10. - Click Save.
- Repeat this process for the second (
rx2.sparkpostmail.com) and third (rx3.sparkpostmail.com) MX records, each with priority10.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
inbound, not inbound.company.com).Verify Your Inbound Domain
After adding all three MX records, go back to Lettr and click Verify DNS Records. DNS propagation can take up to 24–48 hours, though it typically completes within a few hours on Netlify.Tracking Domain Setup
A tracking domain allows Lettr to track email opens and link clicks using your own custom domain instead of the default Lettr tracking domain. This requires two CNAME records: one for the SSL certificate and one for routing tracking traffic to Lettr’s infrastructure.Add Tracking Domain to Lettr
To create a Tracking domain in Lettr:- Select Domains in the navigation panel
- Select Tracking Domains
- Click Create Tracking Domain
- Enter your desired tracking subdomain (e.g.
tracking.company.com) - Click Create Domain
Add SSL Certificate CNAME Record
The SSL Certificate CNAME record provisions an SSL certificate for your custom tracking domain, enabling secure HTTPS connections for tracked links. Add the record in Netlify:- Click Add new record in the DNS records section.
- Set Type to CNAME.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix).
- Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
tracking, not tracking.company.com).Add Traffic CNAME Record
The Traffic CNAME record routes click and open tracking requests from your custom domain to Lettr’s tracking servers. Add the record in Netlify:- Click Add new record in the DNS records section.
- Set Type to CNAME.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix).
- Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
tracking, not tracking.company.com).Verify Your Tracking Domain
After adding both CNAME records, go back to Lettr and click Verify DNS Records.Storage Domain Setup
A storage domain lets you serve email assets (images, attachments) from your own custom domain instead of the default Lettr storage URL. This requires two TXT records for certificate validation and ownership verification, and a CNAME record for routing asset requests to Lettr’s storage infrastructure.Add Storage Domain to Lettr
To create a Storage domain in Lettr:- Select Domains in the navigation panel
- Select Storage Domains
- Click Create Storage Domain
- Enter your desired storage subdomain (e.g.
assets.company.com) - Click Create Domain
Add TXT Record (Certificate Validation)
The Certificate Validation TXT record provisions an SSL certificate for your custom storage domain, enabling secure HTTPS delivery of email assets. Add the record in Netlify:- Click Add new record in the DNS records section.
- Set Type to TXT.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix).
- Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
assets, not assets.company.com).Add TXT Record (Hostname Pre-validation)
The Hostname Pre-validation TXT record verifies ownership of the storage domain before Lettr provisions a custom hostname for it. Add the record in Netlify:- Click Add new record in the DNS records section.
- Set Type to TXT.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix).
- Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
assets, not assets.company.com).Add CNAME Record (Domain Routing)
The Domain Routing CNAME record routes asset requests from your custom domain to Lettr’s storage infrastructure. Add the record in Netlify:- Click Add new record in the DNS records section.
- Set Type to CNAME.
- Copy the Hostname from Lettr and paste it into the Name field (without your domain suffix).
- Copy the Value from Lettr and paste it into the Value field.
- Click Save.
Netlify automatically appends your domain to the record name. Always paste only the subdomain portion (e.g.
assets, not assets.company.com).Verify Your Storage Domain
After adding all three records, go back to Lettr and click Verify DNS Records.Troubleshooting
Domain Suffix Not Omitted
Domain Suffix Not Omitted
Netlify automatically appends your domain to the record name. If you paste the full hostname (e.g.
mailing.company.com), the resulting record will resolve as mailing.company.com.company.com, which will fail
verification.Always paste only the subdomain portion (e.g. mailing, scph0126._domainkey.mailing, _dmarc.mailing).Subdomain Conflicts with Netlify Site
Subdomain Conflicts with Netlify Site
When you assign a domain to a Netlify site, Netlify automatically creates proprietary NETLIFY or NETLIFYv6 records
for that subdomain. If a subdomain you want to use for Lettr (e.g.
mailing.company.com) is already assigned to a
Netlify site, you may need to disconnect the site from that domain before adding DNS records for Lettr. Remove the
site assignment first, or use a different subdomain.Records Not Propagating
Records Not Propagating
DNS propagation on Netlify typically takes a few hours, but can occasionally take longer. If verification fails
after adding records, check the following:
- Wait at least 30 minutes before your first verification attempt.
- Confirm the records exist using command-line tools:
- Use a web tool like dnschecker.org to verify propagation across multiple DNS servers worldwide.
Wrong Record Type
Wrong Record Type
A common mistake is selecting the wrong record type:
| Record | Correct Type |
|---|---|
| Sending verification | CNAME |
| DKIM | TXT |
| DMARC | TXT |
| Inbound mail | MX |
| Tracking SSL certificate | CNAME |
| Tracking traffic | CNAME |
| Storage certificate validation | TXT |
| Storage hostname pre-validation | TXT |
| Storage domain routing | CNAME |
DKIM Value Truncated
DKIM Value Truncated
The DKIM TXT value is a long string. After saving the record, click on it in the DNS records list to confirm the
full value was stored. If it appears truncated, note that Netlify does not support in-place record editing — add
a new record with the correct full value, then delete the old one.
Nameservers Not Pointing to Netlify
Nameservers Not Pointing to Netlify
If your records are saved in Netlify but not resolving, confirm that your domain registrar is pointing to
Netlify’s nameservers. You can check this with:The output should include Netlify’s nameservers in the format
dns1.p0X.nsone.net through dns4.p0X.nsone.net.
Your domain’s exact nameservers are shown in the Name servers panel on the domain’s DNS page in the Netlify
dashboard. If the output shows a different provider’s nameservers, update them at your domain registrar.When to Contact Support
When to Contact Support
If your DNS records are correctly configured (confirmed with
dig or dnschecker.org) and verification still fails
after 48 hours, contact Lettr support at support@lettr.com or through the in-app chat. Include your domain
name and the output of the dig commands above.Related Topics
Sending Domains
Learn about sending domain setup, SPF, DKIM, and DMARC.
Inbound Domains
Configure MX records to receive emails with Lettr.
Tracking Domains
Set up a custom tracking domain for click and open tracking.
Storage Domains
Serve email assets from your own custom domain.
Domains Overview
Understand domain types and how they work in Lettr.
Domain Verification Failures
Troubleshoot common DNS configuration and propagation issues.