Google and Yahoo Email Sender Requirements

Effective Date: January 31, 2024

In October 2023, Google and Yahoo announced new email authentication requirements that took effect in February 2024. Together, these two providers handle approximately 70% of consumer email in the United States. If you’re sending bulk email, compliance isn’t optional—it’s the difference between reaching the inbox and getting blocked.

This guide covers everything you need to know to meet these requirements and keep your emails delivered.

Overview

The requirements target bulk senders—domains sending 5,000 or more emails per day to Gmail or Yahoo addresses. But even smaller senders should comply, as authentication improves deliverability for everyone and requirements may expand.

Quick Summary: What’s Required

Requirement	All Senders	Bulk Senders (5,000+/day)
SPF	Required	Required
DKIM	Required	Required
DMARC	Recommended	Required (minimum p=none)
DMARC Alignment	Recommended	Required (SPF or DKIM must align)
One-Click Unsubscribe	Recommended	Required (marketing emails only)
Spam Rate	Below 0.3%	Below 0.1% (target)
Valid PTR Records	Required	Required
TLS Encryption	Required	Required

The Requirements

1. Email Authentication

All email senders must implement SPF, DKIM, and DMARC. Bulk senders have stricter requirements around DMARC alignment.

SPF (Sender Policy Framework)

SPF specifies which servers are authorized to send email for your domain.

What you need:

Type: TXT
Host: @
Value: v=spf1 include:_spf.google.com include:sendgrid.net -all

Key points:

Only one SPF record per domain (combine all includes)
Maximum 10 DNS lookups allowed
End with -all (hard fail) for best protection
Include all legitimate sending sources (ESPs, CRM, marketing tools)

Verify your SPF:

dig +short TXT example.com | grep spf

DKIM (DomainKeys Identified Mail)

DKIM adds a cryptographic signature to verify email integrity and sender authenticity.

What you need:

DKIM signing enabled for all sending sources
Public key published in DNS
Signature domain should match your From address domain (for alignment)

Verify your DKIM:

dig +short TXT selector._domainkey.example.com

Replace selector with your actual DKIM selector (e.g., google, s1, k1).

DMARC (Domain-based Message Authentication, Reporting & Conformance)

DMARC is required for bulk senders. It ties SPF and DKIM together and tells receivers what to do with failing emails.

Minimum required record:

Type: TXT
Host: _dmarc
Value: v=DMARC1; p=none; rua=mailto:[email protected]

Recommended record (with full reporting):

v=DMARC1; p=none; rua=mailto:[email protected]; ruf=mailto:[email protected]; adkim=r; aspf=r; pct=100

DMARC policy values:

Policy	Meaning	When to Use
`p=none`	Monitor only	Starting out, meets minimum requirement
`p=quarantine`	Send failures to spam	After verifying legitimate sources
`p=reject`	Block failures entirely	Full enforcement (recommended goal)

DMARC Alignment (Critical for Bulk Senders)

This is where many senders fail. DMARC alignment means the domain in your From header must match the domain verified by SPF or DKIM.

SPF Alignment:

The Return-Path domain (envelope sender) must match your From domain
Many ESPs use their own Return-Path by default—you may need custom configuration

DKIM Alignment:

The d= domain in the DKIM signature must match your From domain
Most ESPs support custom DKIM signing on your domain

You need at least one to align. Both is better.

Example of aligned vs. unaligned:

Scenario	From Header	DKIM d=	SPF Domain	Aligned?
Aligned (DKIM)	[email protected]	example.com	esp.com	✅ Yes
Aligned (SPF)	[email protected]	esp.com	example.com	✅ Yes
Not Aligned	[email protected]	esp.com	esp.com	❌ No

2. Easy Unsubscribe

Bulk senders must include a one-click unsubscribe mechanism for marketing and promotional emails.

What’s Required

List-Unsubscribe header with mailto: and/or HTTPS URL
List-Unsubscribe-Post header for one-click functionality
Process unsubscribe requests within 2 days

Example Headers

List-Unsubscribe: &lt;mailto:[email protected]&gt;, &lt;https://example.com/unsubscribe?id=123&gt;
List-Unsubscribe-Post: List-Unsubscribe=One-Click

What This Looks Like to Recipients

Gmail and Yahoo display an “Unsubscribe” link near the sender name:

From: Newsletter <[email protected]> Unsubscribe · to me

ESP Support

Most email service providers handle this automatically:

ESP	One-Click Unsubscribe
Mailchimp	Automatic for all campaigns
SendGrid	Automatic with subscription tracking enabled
HubSpot	Automatic for marketing emails
Klaviyo	Automatic for all sends
Amazon SES	Manual configuration required

Check your ESP’s documentation if you’re not seeing these headers.

Transactional Exemption

One-click unsubscribe is not required for:

Order confirmations
Shipping notifications
Password resets
Account alerts
Other transactional messages

3. Low Spam Complaint Rates

The Thresholds

Provider	Target Rate	Maximum Rate
Google	Below 0.10%	Never exceed 0.30%
Yahoo	Below 0.30%	Not specified

How Spam Rate Is Calculated

Spam rate = (Emails marked as spam) / (Emails delivered to inbox)

A rate of 0.10% means 1 spam complaint per 1,000 emails delivered.

Monitoring Your Spam Rate

Google Postmaster Tools (essential for Gmail senders):

Go to Google Postmaster Tools
Add and verify your domain
Monitor spam rate, IP reputation, and authentication status

Yahoo Complaint Feedback Loop:

Register at Yahoo Postmaster
Set up feedback loop to receive complaint notifications

Reducing Spam Complaints

Clean your list regularly: Remove inactive subscribers (no opens in 6+ months)
Honor unsubscribes immediately: Don’t wait the full 2 days
Set expectations: Be clear about email frequency at signup
Segment your sends: Don’t blast everyone with everything
Make unsubscribe easy: Don’t hide it or require login

Who This Affects

Google’s Definition of Bulk Sender

Any domain that sends close to 5,000 messages or more to personal Gmail accounts in a 24-hour period. Critical details:

Once you reach this threshold even once, you’re permanently classified as a bulk sender
The count is per sending domain, not per email address
Internal Google Workspace emails may count toward the limit
Third-party sends (via ESPs like Mailchimp or SendGrid) using your domain count toward your total

Yahoo’s Definition

Yahoo hasn’t specified an exact threshold. They classify bulk senders based on “significant volume” to Yahoo addresses. Assume similar thresholds apply.

Even If You’re Under 5,000

You should still comply because:

Yahoo doesn’t have a firm threshold—you might already be classified
You could hit 5,000 during peak periods (Black Friday, product launches)
Requirements may expand to all senders
Authentication improves deliverability regardless of volume

Implementation Checklist

For All Senders

SPF record published with all legitimate sending sources
DKIM enabled for all email streams (marketing, transactional, etc.)
DMARC record published (at minimum p=none with reporting)
Valid PTR records for sending IPs
TLS enabled for email transmission
Valid From addresses that can receive replies

Additional for Bulk Senders (5,000+/day)

DMARC alignment achieved (SPF or DKIM aligns with From domain)
One-click unsubscribe implemented for marketing emails
Google Postmaster Tools set up and monitored
Yahoo Feedback Loop registered
Spam rate maintained below 0.10% (target) / 0.30% (max)
Unsubscribes processed within 2 days

Common Mistakes

”DMARC is passing but emails still go to spam”

DMARC passing doesn’t guarantee inbox placement. Other factors matter:

Sender reputation (built over time)
Content quality and relevance
Engagement rates (opens, clicks)
Spam complaint history

”SPF is failing for my ESP”

Your ESP’s sending IPs might not be in your SPF record. Add their include statement:

ESP	SPF Include
SendGrid	`include:sendgrid.net`
Mailchimp	`include:servers.mcsv.net`
Amazon SES	`include:amazonses.com`
Google Workspace	`include:_spf.google.com`
HubSpot	`include:spf.hubspot.com`

”DKIM alignment is failing”

Your ESP might be signing with their domain, not yours. Enable custom DKIM:

Most ESPs support this via CNAME records in your DNS
Check your ESP’s domain authentication settings
You typically need to add 2-3 DNS records

”I exceeded the SPF lookup limit”

SPF allows maximum 10 DNS lookups. Solutions:

Remove unused include statements
Use SPF flattening (convert includes to IPs)—requires ongoing maintenance
Use subdomains for different sending streams

”One-click unsubscribe isn’t showing in Gmail”

Check that:

Your ESP has subscription tracking enabled
The email is classified as promotional (not transactional)
The List-Unsubscribe-Post header is present
You’re not using a suppression list that bypasses the header

Monitoring Compliance

Ongoing Monitoring Tasks

Task	Frequency	Tool
Check spam rate	Daily	Google Postmaster Tools
Review DMARC reports	Weekly	DMARC monitoring service
Verify DNS records	Monthly	dig / MXToolbox
Audit sending sources	Quarterly	DMARC reports

Warning Signs

Watch for these indicators of compliance issues:

Sudden drop in open rates (especially Gmail)
Increase in bounces with 5.7.x error codes
Spam rate creeping above 0.10%
New sending sources appearing in DMARC reports
DMARC failures increasing

Google-Specific Error Codes

Error Code	Meaning	Action
`421-4.7.28`	Temporary failure, authentication issue	Check SPF/DKIM/DMARC
`550-5.7.26`	Unauthenticated email not accepted	Fix authentication immediately
`550-5.7.1`	Message rejected due to spam	Check content and reputation

How Verkh Helps

Verkh monitors your email authentication and helps you reach full DMARC enforcement.

What you get:

Real-time monitoring of SPF, DKIM, and DMARC status
Sending source identification — see every service sending as your domain
Guided remediation — copy-paste DNS records to fix issues
Shareable dashboards — send live reports to vendors who need to fix their authentication
Progress tracking — know when you’re ready to move from p=none to p=reject

The destination is enforcement. We walk with you until you get there.

Start Free →

Resources

Official Documentation

Testing Tools

Timeline Reference

Date	Milestone
October 3, 2023	Google and Yahoo announce requirements
February 1, 2024	Initial enforcement begins—temporary errors for non-compliance
April 2024	Google begins rejecting percentage of non-compliant email
June 1, 2024	One-click unsubscribe deadline for bulk senders

Last updated: January 2025. Requirements may change—check provider documentation for the latest information.