Starting in 2024, email senders must meet specific requirements to send email to Gmail personal accounts (@gmail.com or @googlemail.com). These guidelines help ensure the successful delivery of messages and reduce the risk of them being blocked or marked as spam.
Requirements for all senders (any volume)
Set up SPF or DKIM email authentication for your sending domains
Ensure sending domains/IPs have valid forward and reverse DNS (PTR) records
Use a TLS connection for transmitting email
Keep spam rates reported in Postmaster Tools below 0.3%
Format messages according to the RFC 5322 standard
Requirements for high-volume senders (5,000+ messages/day)
Set up SPF and DKIM email authentication
Set up DMARC email authentication (enforcement policy can be set to "none")
The domain in the sender's From: header must align with either the SPF domain or the DKIM domain (required to pass DMARC)
Marketing messages must support one-click unsubscribe and include a clearly visible unsubscribe link in the message body
Infrastructure requirements and guidelines
IP address configuration
The sending IP address must match the IP address of the hostname specified in the pointer (PTR) record
Set up valid reverse DNS records pointing to your domain
Shared IP considerations
The activity of any sender using a shared IP address affects the reputation of all senders for that shared IP address
Verify the shared IP isn't on any blocklist
Monitor shared IP reputation through Postmaster Tools
Content guidelines
Format HTML messages according to HTML standards
Don't use HTML and CSS to hide content in your messages
Make web links visible and easy to understand
Keep sender information clear and visible
Display name best practices
What to do
Display names should reflect a consistent, clear, and accurate statement of the sender's identity
Use display names exclusively to identify the sender
Maintain consistency across messages
What to avoid
Don't include subject or message content in display names
Avoid misleading names like "URGENT REQUEST" or "Last Chance"
Don't include the recipient's name in the display name
Display names should never be used to deceive the recipient
Subscription management
One-click unsubscribe setup
For high-volume senders, include both headers:
List-Unsubscribe-Post: List-Unsubscribe=One-Click
List-Unsubscribe: <https://yourdomain.com/unsubscribe/example>
Default behavior in Blueshift
One-click list unsubscribe is enabled by default in Blueshift unless the list-unsubscribe header is manually disabled for the campaign.
Best practices
Make it easy for recipients to opt in with confirmed email addresses
Provide easy unsubscribe options
Consider unsubscribing recipients who don't engage
Send only to people who want your messages
Monitoring & compliance
Regularly check Google Postmaster Tools for current reputation status and delivery errors
Keep spam rates reported in Postmaster Tools below 0.10% and avoid reaching a spam rate of 0.30% or higher
Monitor overall compliance status on the Google Sender Compliance page: https://postmaster.google.com/v2/sender_compliance
Check domain status with Google Safe Browsing regularly
Use the Google Admin Toolbox to review DNS and fix domain settings
Helpful tools for monitoring
Gmail – email delivery issues
If you are experiencing lower delivery rates due to soft bounces, Gmail may be rejecting messages. Common Gmail error messages include:
421, "4.7.0": Messages are rejected because the sending server’s IP address is not on the allowed list for the recipient’s domain.
550, "5.7.1": Messages are rejected because the sending server’s IP address is on an IP suspended list. This can happen when using a shared IP with poor reputation.
Related sender guidelines
While each major ISP has similar recommendations, there can be variations in documented guidelines. Reviewing them together can help improve deliverability.
For more details, refer to the following sender guidelines:
Microsoft sender guidelines (coming soon)