The new Gmail, Yahoo, and Microsoft rules reshaping email marketing
Date
22 June 2026
by Carolina Bellogi and Benedetta Tubaldo
In recent months, Gmail, Yahoo, and Microsoft have introduced significant changes to bulk emailing regulations, aimed at protecting users from spam, phishing, and unsolicited communications.
For businesses that rely on email marketing as a strategic communication driver, these updates simply cannot be ignored: compliance with the new regulations will determine whether emails actually reach the recipients’ inboxes or vanish invisibly into the spam folder.
What we will cover in this article:
- Why providers are tightening email regulations
- The new rules for bulk email senders
- Authentication becomes mandatory
- Sender and domain must remain aligned
- Easy unsubscription to avoid the spam folder
- The role of domain reputation: trust opens the inbox
- Why these changes directly impact email marketing
- How SAY supports businesses with email marketing
- A change that can be turned into an opportunity
Why providers are tightening email regulations
In recent years, the volume of emails circulating globally every day has grown exponentially. Billions of messages are sent daily, but a significant portion of them consists of spam or phishing attempts.
As a result, email service providers have tightened their control systems to protect users and make the entire email ecosystem more secure.
Gmail, Yahoo, and Microsoft are all moving in the same direction: simplifying the process of identifying trustworthy senders and blocking suspicious ones.
For those involved in email marketing, this shift essentially boils down to one thing: the need to clearly prove who is sending a message and why.
In other words, electronic mail is increasingly resembling a building with an identity check at the entrance: anyone arriving must show a valid badge before being allowed inside.
The new rules for bulk email senders
Starting from 2024, Gmail and Yahoo introduced new requirements for so – called bulk senders – those sending more than 5,000 emails a day. Microsoft has progressively adopted very similar criteria across its Outlook, Hotmail, and Live services.
The main updates cover three areas:
- Email authentication
- Alignment between domain and sender
- Proper unsubscription management
These requirements are designed to ensure that emails truly come from who they claim to be from, and that users can easily manage the communications they receive.
For businesses, this means paying closer attention to both the technical configuration of domains and sending platforms, and the way contact lists are managed.
Authentication becomes mandatory
The most significant change concerns email authentication.
When an email arrives at a mail server, the provider checks specific technical elements to determine whether the sender is trustworthy. If these checks fail, the message may be filtered or rejected.
This is why Gmail, Yahoo, and Microsoft now require the use of three verification systems: SPF, DKIM, and DMARC.
At first glance, these acronyms might seem complex, but how they work is fairly intuitive: we can think of them as three distinct security checks.
SPF: the list of authorised tools
SPF, which stands for Sender Policy Framework, functions as an official list of the tools authorised to send emails on behalf of a domain.
When a business uses an email marketing platform, the domain must declare to the mail servers that this platform is authorised to send messages.
To draw a comparison, it is like saying: ‘These are the couriers authorised to deliver parcels on my behalf.’ If a message arrives from a system that is not included in the list, the provider will consider it suspicious.
DKIM: the email’s digital signature
DKIM, which stands for DomainKeys Identified Mail, adds a digital signature to the message.
This signature allows the receiving mail server to verify that the content has not been modified during transit. We can think of it as a seal on an important letter: if the seal is intact, the recipient knows that the content has not been altered along the way.
Conversely, if the check fails, the provider can decide to block or filter the message.
DMARC: the final control system
DMARC, which stands for Domain-based Message Authentication, Reporting and Conformance, adds an additional layer of security.
This protocol instructs providers on what to do when an email fails SPF or DKIM checks. Furthermore, it allows the domain owner to receive reports on any attempts at abuse or impersonation.
In practice, DMARC acts as a supervisor: it monitors what happens to the domain’s emails and reports any suspicious activity.
Sender and domain must remain aligned
Another rule being tightened by providers concerns the alignment between the domain used to send the emails and the one displayed in the sender field.
This measure is designed to counter spoofing, a highly widespread technique in online scams. Spoofing occurs when an email appears to come from a specific sender, but has actually been sent from an entirely different system.
For providers, it is somewhat like receiving a letter signed by a bank but posted from a completely unrelated address: it is a clear sign that something might not be trustworthy.
For this reason, Gmail, Yahoo, and Microsoft require the sending domain to be aligned with the one used in the sender field and authentication signatures.
Easy unsubscription to avoid the spam folder
Another requirement introduced by the new guidelines concerns unsubscription management.
Promotional emails must include a clear and easily accessible cancellation system. In many cases, the so-called ‘one-click unsubscribe’ is also required – meaning the ability to unsubscribe with a single click.
Making the newsletter unsubscription process easy is also strategic: it prevents users from marking emails as spam when they simply want to stop receiving them. It is a minor technical adjustment, but it has a major impact on domain reputation and the overall quality of communications.
The role of domain reputation: trust opens the inbox
Beyond technical checks, providers closely monitor user behaviour.
If many people open emails, click on links, or interact with the message, the domain is deemed trustworthy. Conversely, if users ignore messages or mark them as spam, the sender’s reputation drops.
We can think of domain reputation as that of a shop on a busy high street. If the shop is well-known, people happily go inside and speak highly of their experience, making it a landmark. But if customers leave annoyed or stop entering altogether, trust plummets rapidly.
Mail providers reason in a similar way: when emails from a domain are opened and generate interaction, that sender is considered reliable, and messages reach the main inbox more easily. On the other hand, if users ignore them or report them as spam, trust erodes and filters become stricter.
Why these changes directly impact email marketing
For businesses that use newsletters and email automation in their communication and sales processes, these new rules have a major impact.
If domain authentication is not configured properly, or if the sender’s reputation is low, campaigns can suffer from deliverability issues.
Deliverability is an email’s ability to reach the recipient’s main inbox.
Pressing ‘send’ is no longer enough: you must ensure that the message passes all provider checks and is considered trustworthy.
This means that today, email marketing requires more careful management from both a technical and a strategic perspective.
How SAY supports businesses with email marketing
The new rules introduced by Gmail, Yahoo, and Microsoft are making email marketing increasingly structured and professional.
This is why many businesses choose to manage their newsletters and campaigns with the support of specialised partners.
At SAY, we help brands design and optimise effective email marketing strategies, starting precisely with the aspects that have the greatest impact on deliverability today.
Our work includes verifying the technical configuration of sending domains, optimising campaign platforms, and designing editorial strategies for newsletters and email automations.
Added to this is continuous performance monitoring, which helps improve communication quality and domain reputation over time.
A change that can be turned into an opportunity
With the new rules introduced by providers, the email ecosystem is becoming increasingly selective. Messages sent without proper configurations or a clear strategy are struggling more than ever to reach users’ inboxes.
At the same time, businesses investing in professional email marketing management can achieve better results than in the past.
When technical authentication, content quality, and list management work together, newsletters once again become one of the most effective tools for building relationships with customers and prospects.
If you want to understand how to adapt your campaigns to the new guidelines from Gmail, Yahoo, and Microsoft, we can help you analyse your sending system and design a truly effective email marketing strategy.
