Contents
- Three major platforms are raising the bar for bulk email
- Email authentication is no longer optional
- Spam thresholds are being monitored more closely than ever
- Unsubscribe must be visible, easy to use, and easy to complete
- A perspective for the Vietnamese market
- What should Vietnamese marketers do?
- Reference
As of July 2026, Google, Yahoo, and Microsoft simultaneously raising the bar for bulk email is no longer just a technical story — it has become a decisive factor in revenue from the email channel. As filters grow stricter, inbox placement (deliverability) directly determines the effectiveness of every CRM, lead nurturing, and automation campaign. For Vietnamese marketers, this is the moment to view email as a reputation asset that must be protected, rather than a channel for “blasting” at scale — because even a list with many Gmail or Outlook users can instantly change sending performance.
Google, Yahoo, and Microsoft are all tightening standards for bulk email, and this directly affects how marketers run CRM, lead nurturing, and email automation campaigns. For brands that rely heavily on email to generate revenue, failing to meet the new standards can cause messages to be blocked, land in junk, or lose access to target recipients.
What is notable is that these requirements are not limited to authentication technology; they also touch content quality and recipient experience. In other words, beyond email infrastructure, marketing teams need to review the entire sending strategy to avoid being flagged as spam.
Three major platforms are raising the bar for bulk email
According to MarTech, Google and Yahoo began enforcing new requirements from February 1, 2024 for bulk email senders. Google defines this group as senders of more than 5,000 emails per day to Gmail addresses. By April 2024, Google moved to a tougher step: not only issuing warnings, but beginning to reject some non-compliant email traffic and gradually increasing the blocking rate over time.
Microsoft later applied a similar policy to Outlook.com domains, including hotmail.com and live.com. Initially, Microsoft planned to move non-compliant mail to Junk, but later adjusted to fully reject bulk emails that do not meet the requirements starting May 5, 2025.
In essence, this is an industry-wide “standardization” effort to reduce email abuse, limit spoofing, and improve inbox quality for end users.
Email authentication is no longer optional
All three giants require bulk email senders to fully implement three layers of authentication: SPF, DKIM, and DMARC. This is the basic toolkit that helps prove an email was sent from a legitimate server, was not altered in transit, and allows the domain owner to specify how to handle authentication failures.
- SPF helps determine which servers are allowed to send email on behalf of a domain.
- DKIM adds a digital signature to prove the message is valid and has not been tampered with.
- DMARC connects the two layers above, while also providing reports and handling policies when email authentication fails.
For marketers, this is no longer a “nice-to-have technical item” but a minimum condition for maintaining deliverability. If the email marketing system, subdomains, or third-party senders are not configured in sync, the risk of being blocked will rise significantly.
Spam thresholds are being monitored more closely than ever
Google requires bulk senders to keep the spam report rate in Google Postmaster Tools below 0.10% and to “avoid ever reaching 0.30% or higher.” This is an extremely low figure, showing how sensitive filtering systems are today. In other words, even if only a small portion of recipients report a message as spam, a brand’s sending reputation can already be affected.
The challenge is that spam reports are not determined entirely by infrastructure, but also depend heavily on how recipients perceive the value of the email. MarTech quoted Dana Carr, Email Marketing Director at Optimove, who said send time is a noteworthy factor: many bulk email campaigns are sent at the beginning or end of the hour, unintentionally creating a sense of overload and making them easier to ignore or mark as spam.
She also emphasized the role of the preference center — a section that lets users choose their email frequency, topics of interest, and product categories. This approach not only helps reduce sending frequency but often increases engagement because the content is more relevant to recipients’ actual needs.
Unsubscribe must be visible, easy to use, and easy to complete
One of the main focuses of the new rules is unsubscribe functionality. Google, Yahoo, and Microsoft all want users to be able to leave mailing lists simply, rather than having to search for an unsubscribe button buried deep in the email or go through multiple cumbersome steps.
For businesses, this is a reminder that a high-quality email list matters more than a large but low-engagement one. A transparent unsubscribe process may reduce the number of people leaving the list, but it helps retain those who are genuinely interested — the group most likely to open, click, and convert.
Viewed long term, optimizing unsubscribe does not reduce campaign effectiveness; it helps clean the database and improve the quality of every send. That is the foundation for protecting deliverability in a landscape where filters are becoming increasingly “picky.”
A perspective for the Vietnamese market
For Vietnamese marketers, this change is especially important if the business uses Gmail, Outlook, or Yahoo as the primary destination in CRM, e-commerce, B2B nurturing, or email automation campaigns. Although the rules were issued by international platforms, their impact is global: as long as a list has a large share of Gmail/Outlook users, sending performance can change immediately.
The immediate next step is to review SPF, DKIM, and DMARC; check spam rates in monitoring tools; and reassess the unsubscribe journey to ensure users can leave the list easily. More importantly, marketing teams need to shift their focus from “sending more” to “sending to the right people, at the right time, with the right expectations.” This is the sustainable path in an email environment that is being tightened more aggressively.
If a business depends heavily on email to drive conversions, now is the right time for marketing, IT, and CRM teams to work together to standardize the sending system before it is affected by increasingly strict filters.
What should Vietnamese marketers do?
- Review and synchronize SPF, DKIM, and DMARC for every domain and third-party sender before running the next bulk campaign.
- Monitor spam rates in Google Postmaster Tools, keep them below 0.1%, and absolutely do not let them reach the 0.3% threshold.
- Set up a preference center so recipients can choose frequency and topics, reducing the risk of being marked as spam.
- Make sure the unsubscribe button is easy to see and uses a one-click mechanism, instead of hiding it deep inside the email.
- Review send timing and frequency; prioritize “sending to the right people, at the right time” instead of blasting messages at the beginning or end of the hour.
Overall, this wave of stricter standards is not meant to eliminate email marketing, but to force businesses to shift from a quantity mindset to a quality mindset. For marketers, the teams that coordinate marketing, IT, and CRM early to standardize their sending systems will retain a deliverability advantage — something that is becoming increasingly scarce as inboxes around the world close their doors to non-compliant senders.
