Email sender guidelines FAQ

A bulk sender is any email sender that sends close to 5,000 messages or more to personal Gmail accounts within a 24-hour period. Messages sent from the same primary domain count toward the 5,000 limit.

Sending domains: When we calculate the 5,000-message limit, we count all messages sent from the same primary domain. For example, every day you send 2,500 messages from solarmora.com and 2,500 messages from promotions.solarmora.com to personal Gmail accounts. You’re considered a bulk sender because all 5,000 messages were sent from the same primary domain: solarmora.com. Learn about domain name basics.

Senders who meet the above criteria at least once are permanently considered bulk senders.

Bulk sender status doesn’t have an expiration date. Email senders that have been classified as bulk senders are permanently classified as such. Changes in email sending practices will not affect permanent bulk sender status once it’s assigned.

Bulk senders should use Postmaster Tools to check that their email practices are following our Email sender guidelines. To learn more, visit our Email sender requirements & Postmaster Tools FAQ.

The Email sender guidelines don’t apply to messages sent to Google Workspace accounts. Sender requirements and Google enforcement apply only when sending email to personal Gmail accounts.

All senders, including Google Workspace users, must meet the requirements in our Email sender guidelines when sending messages to personal Gmail accounts. The requirements don’t apply to Google Workspace inbound and intra-domain messages.

A new domain is defined as any domain that hasn’t sent more than 5,000 emails a day to personal Gmail accounts since January 1, 2024.

While all bulk sending domains must comply with the requirements, the enforcement progression for new domains will be on an accelerated timetable.

Gmail From: header impersonation is when a sender sends a message with a @gmail address in the From: header but the message wasn’t sent from a Gmail server. This is a common form of email abuse by spammers and is referred to as spoofing.

As described in the timeline above, bulk senders that spoof gmail.com will start getting notifications about temporary failures.

Yes, when messages are rejected, we send a rejection code and a reason for the rejection. You can also see this information in Postmaster Tools.

Temporary failure messages include error codes that indicate which sender requirement is causing the failure:

Spam rate is calculated daily. To help ensure messages are delivered as expected, senders should keep their spam rate below 0.1% and should prevent spam rates from ever reaching 0.3% or higher, as described in our Email sender guidelines.

To comply with the sender guidelines, keep your user-reported spam rate below 0.1% and prevent it from reaching 0.3% or higher.

The user-reported spam rate’s impact on delivery is graduated, and rates of 0.3% or higher have an even greater negative impact on email inbox delivery. Even today, user-reported spam rates greater than 0.1% have a negative impact on email inbox delivery for bulk senders.

Beginning June 2024, bulk senders with a user-reported spam rate greater than 0.3% will be ineligible for mitigation.

• Bulk senders remain ineligible for mitigation while user-reported spam rate is greater than 0.3%.
• Spam rates and other data points are calculated and updated daily in Postmaster Tools.
• Bulk senders will be eligible for mitigation when their spam rates remain below 0.3% for 7 consecutive days.

You can monitor your spam rate with Postmaster Tools.

No. One-click unsubscribe is required only for marketing and promotional messages. Transactional messages are excluded from this requirement. Some examples of transactional messages are password reset messages, reservation confirmations, and form submission confirmations.

Senders that already include an unsubscribe link in their messages have until June 1, 2024 to implement one-click unsubscribe in all commercial, promotional messages.

To protect Gmail users, unsubscribe buttons or links are displayed at the top of messages (next to the sender name) only for messages that pass Google’s automated eligibility checks. Messages must comply with sender requirements and implement correct one-click unsubscribe headers, as described in our Email sender guidelines, including increasing sending volumes gradually and monitoring recipients' spam reports. This is true even when senders add their own unsubscribe link to the message body.

The distinction between promotional and transactional messages can vary depending on industry and applicable regulations. Message recipients, not Google, determine the nature of the messages they receive. To reduce high spam rates, consider giving users an easy way to unsubscribe from marketing and promotional messages, and keep the user in mind when designing your emails.

One-click unsubscribe lets people quickly and easily opt out of your marketing or promotional messages. One-click unsubscribe also helps you maintain a low spam rate, which improves message delivery. High spam rates negatively affect message delivery for any message type that you send.

To meet RFC 8058 requirements, add List-Unsubscribe headers to all outgoing marketing and promotional messages, as described in our Email sender guidelines. If you use a third-party email provider, check to see if you have the option to add these headers to your outgoing messages.

List-Unsubscribe headers unsubscribe users directly by removing them from the mailing list. Other types of one-click unsubscribe, such as mailto and URL unsubscribe links, don’t meet our one-click unsubscribe requirement.

We don’t automatically reject messages or mark messages as spam when they don’t meet the one-click unsubscribe requirements in our Email sender guidelines.

However, unwanted messages that don’t use one-click unsubscribe are more likely to be reported as spam by recipients. An increase in messages marked as spam increases the chances that future messages from the same sender are delivered to spam.

Additionally, only bulk senders that meet all the requirements in our Email sender guidelines, including one-click unsubscribe, are eligible for mitigation.

No. One-click unsubscribe should be implemented according to RFC 8058, by adding List Unsubscribe headers to outgoing promotional messages, as described in our Email sender guidelines. Including a mailto link in the body of your messages doesn’t meet our one-click unsubscribe requirement.

No. If your messages include a one-click unsubscribe using List Unsubscribe headers, as described in our Email sender guidelines, additional unsubscribe links in the message body aren’t required to be one-click. Any additional unsubscribe links in the message body can link to a preferences web page that you specify.

To reduce spam reports, protect your sending reputation, and keep your email lists healthy, we recommend that you fulfill unsubscribe requests within 48 hours, a reasonable timeline for removing recipients from a mailing list.

Honoring unsubscribe requests from recipients is especially critical if you frequently send marketing messages. This results in improved email delivery and higher value for engaged people who want to get messages from you.

One-click unsubscribe doesn’t automatically remove the recipient from all messages from the same sender. When you implement one-click unsubscribe according to RFC 8058, by using List Unsubscribe headers as described in our Email sender guidelines, the recipient can be removed only from the mailing list associated with the message. One-click unsubscribe lets you control which mailing lists recipients are removed from.

If you meet the one-click unsubscribe requirement, you can also include an unsubscribe link in the message body that directs people to a mailing list preferences page. Be aware that this type of link doesn’t comply with RFC 8058, and so using this type of link alone, without one-click unsubscribe email headers, doesn’t meet the one-click unsubscribe requirement as described in our Email sender guidelines.

If your unsubscribe link isn’t working for an extended period of time, your messages won’t meet our one-click unsubscribe requirement. These messages won’t be marked as spam, but senders aren’t eligible for mitigation for email delivery issues.

We’ll continue to support mailto links but they don’t meet our one-click unsubscribe requirement. To meet our one-click unsubscribe requirement, you must use List-Unsubscribe email headers in all commercial, promotional messages, as described in RFC 8058 and in our Email sender guidelines, and include one HTTPS URL in the List-unsubscribe: header.

Senders should follow the specifications for one-click unsubscribe that are defined in RFC 8058, and add List Unsubscribe headers to all outgoing promotional messages, as described in our Email sender guidelines.

Email admins should use RFC 8058 as the reference for implementing one-click unsubscribe. One-click unsubscribe links that link to a landing or other type of web page don’t comply with RFC 8058.

For messages sent directly to personal Gmail accounts, the organizational domain in the sender From: header must be aligned with either the SPF organizational domain or the DKIM organizational domain. Although we require bulk senders to set up both SPF and DKIM authentication, only one of these needs to be aligned to meet the sender alignment requirements.

DMARC alignment isn’t required for forwarded or mailing list messages (sometimes referred to as indirect messages), however we require that these types of messages have ARC headers. Learn more about ARC authentication and headers.

To ensure reliable authentication, we recommend all senders fully align DMARC to both SPF and DKIM. It’s likely that DMARC alignment with both SPF and DKIM will eventually be a sender requirement. Learn more about DMARC alignment.

If messages fail DMARC because of authentication or alignment issues, the enforcement defined in the sending domain’s DMARC policy generally applies. If the sending domain doesn’t have a DMARC policy, the messages might be rejected or sent to spam. Failing DMARC authentication is one of several factors that determine whether messages are rejected, sent to spam, or delivered as expected. DMARC authentication is an important determining factor, and so these messages are typically handled based on the enforcement setting in the sending domain’s DMARC policy.

Learn more about DMARC policies and enforcement options.

Bulk senders that meet all requirements described in our Email sender guidelinescan submit an escalation for email delivery issues. Before contacting tech support, make sure you’re following all sender guidelines. Starting in February 2024, we won’t provide mitigation for email delivery issues to senders that don’t meet the guidelines. For details about mitigation requests, visit the Sender contact form.

Only bulk senders that meet all the requirements in our Email sender guidelines, including authentication requirements, user-reported spam-rate requirements, and one-click unsubscribe for relevant traffic, are eligible for mitigation.