Who This Is For / When to Use
Use this guide if you:
Send bulk email campaigns to Gmail or Yahoo recipients.
Send more than 5,000 emails per day.
Want to prevent emails from being blocked, delayed, or marked as spam.
Are setting up or auditing email deliverability in Kyrios.
Overview of Google and Yahoo Requirements
Google and Yahoo now require all bulk senders to:
Authenticate email with SPF, DKIM, and DMARC.
Use a branded sending domain.
Align the "from" address with the sending domain.
Avoid impersonating Gmail or Yahoo addresses.
Provide an easy unsubscribe option, including one-click unsubscribe.
Maintain a spam complaint rate below 0.30%.
Failure to meet these requirements can result in delivery issues or spam filtering.
Step 1: Set Up a Branded Sending Domain
A branded sending domain improves sender reputation and removes the "sent via msgsndr.com" disclaimer.
Why this matters
Required for bulk senders to Google and Yahoo.
Improves inbox placement and brand recognition.
What to expect
After enabling a branded sending domain, warm up your sending volume over 2–4 weeks.
Example (Gmail view)
Next step Follow the help article: How to Set Up a Dedicated Sending Domain.
Step 2: Configure DMARC Authentication
What is DMARC
DMARC (Domain-based Message Authentication, Reporting, and Conformance) builds on SPF and DKIM to tell mailbox providers how to handle unauthenticated email claiming to come from your domain.
DMARC helps:
Prevent spoofing and phishing.
Improve deliverability trust with Google and Yahoo.
When DMARC Is Required
You must configure DMARC if:
You send more than 5,000 emails per day.
Your domain currently has no DMARC record.
How to Add a DMARC Record
Check your domain using a DMARC checker (for example, Dmarcian).
If no valid record exists, log in to your DNS provider.
Create a new TXT record.
Set the Host/Name to:
_dmarc
Set the TXT Value to:
v=DMARC1; p=none;
Save the record and wait a few minutes for DNS propagation.
DNS example
How to Verify DMARC Is Working
You can verify DMARC by:
Re-running your DMARC checker, or
Sending yourself an email and inspecting the headers in Gmail.
A successful configuration will show SPF, DKIM, and DMARC as passing.
Step 3: Align the "From" Address With Your Domain
Your email "from" address must match the root domain of your branded sending domain.
Example
Branded sending domain:
lc.msgsndr.comRoot domain:
msgsndr.comValid from address:
[email protected]
Misalignment can cause DMARC failures and spam filtering.
Step 4: Do Not Impersonate Gmail or Yahoo
Do not send emails using:
@gmail.com@yahoo.com
Google and Yahoo enforce DMARC quarantine policies on their own domains. Impersonation can result in blocked delivery.
Step 5: Make Unsubscribing Easy
One-Click Unsubscribe (Header-Level)
Kyrios automatically inserts a one-click unsubscribe link into the email headers for all campaign and automation emails (excluding 1:1 emails).
Gmail example
Unsubscribe Link in Email Body
You must also ensure every campaign and flow email includes a visible unsubscribe link in the email body, typically in the footer.
This link does not need to be one-click but must be easy to find and use.
Step 6: Keep Spam Complaints Below 0.30%
High spam complaint rates damage sender reputation.
Best practices
Send emails only to contacts who explicitly opted in.
Remove unengaged contacts regularly.
Monitor complaints and engagement.
Monitoring tools
Yahoo: Spam Reports
Gmail: Google Postmaster Tools
Target fewer than 1 spam complaint per 1,000 emails sent.
Common Issues and Fixes
Emails landing in spam
Verify SPF, DKIM, and DMARC are passing.
Confirm branded sending domain is active.
Reduce sending volume and warm up gradually.
DMARC showing as failed
Check that the host is
_dmarcand not your root domain.Confirm no duplicate DMARC records exist.
Unsubscribe warnings from Gmail
Ensure unsubscribe links exist in both headers and email body.
FAQ
What happens if I do not set up DMARC?
Without DMARC, mailbox providers may mark your emails as spam or block them entirely, especially when sending to Gmail or Yahoo recipients.
How do I make sure my from address is compliant?
Use a from address that matches the root domain of your branded sending domain. Misalignment can cause DMARC failures.
Why is an unsubscribe link required?
Unsubscribe links reduce spam complaints, protect sender reputation, and are mandatory under Google and Yahoo sender policies.
Do I need to manually add the one-click unsubscribe header?
No. Kyrios automatically adds the one-click unsubscribe header to all non–1:1 emails. You only need to confirm there is also a visible unsubscribe link in the email body.
How should I roll out stricter DMARC policies?
Start with p=none, monitor results, then gradually move to quarantine or reject to strengthen protection without disrupting delivery.
How long should I warm up a new sending domain?
Plan a gradual warm-up over 2–4 weeks to build a healthy sender reputation.