Gmail & Yahoo Sender Requirements: All You Need to Know

In February, both Gmail and Yahoo! Mail are rolling out new updates and guidelines for email deliverability. So in our neck of the woods, there are buzzwords like SPF, DKIM, and DMARC being thrown around. While we’ve known about them for a while, we understand that some businesses might not be aware of how they work–or how email authentication works in general.

We’ll cover what email authentication is, what the email sender requirements are, and a bit more in this article.

What is Email Authentication?

Email authentication, at its most basic, is like putting a sophisticated and hard-to-open wax stamp on your messages to your customers and other stakeholders. This security measure ensures that your email has not been tampered with during transit.

When sending an email, providers like Gmail/Yahoo must verify the email sender’s identity.

This protects both your brand and your customers from malicious actors – scammers or phishers who email pretending to be you to extort people for money/info.

If you’re on Klaviyo’s Shared Sending Domain, SPF/DKIM are things you don’t have to care about, because Klaviyo has already sorted it for you.

However, outside of the platform, you see something like this:

And, with the changes rolling out 1 Feb, this has become our top priority for our clients – getting them on a dedicated sending domain (check out Klaviyo’s comprehensive guide here).

Common Authentication Standards

There are three common standards that are integral to email security: SPF, DKIM, and DMARC. These form a tight framework that strengthens communication for businesses big and small.

1) Sender Policy Framework – SPF

The Sender Policy Framework, or SPF, is a security measure that prevents email spoofing, a known scamming practice. When someone receives an email, Gmail or Yahoo! Mail servers check through and verify the sender. 

Below are some major highlights for SPF:

• Designed to detect forged sender addresses during the delivery of the email.
• Helps the receiving mail server verify that emails coming from a specific domain were sent through an IP Address authorized by the domain’s administrators.
• If the email has been sent through an IP address not allowed by SPF, then the email can be rejected or redirected away from the primary inbox
• Without this, people can easily impersonate your brand via email.

2) DomainKeys Identified Mail – DKIM

DKIM is another email authentication method that ensures emails are not tampered with after being sent. Basically, the sender will have a digital signature with a private key while the recipient’s server will verify this through a public key published in the sender’s DNS records. This minimizes the risk of phishing and improves the trust between sender and recipient. 

Here are three more things you should know about DKIM:

• A digital signature is added to the header of your email to further verify the identity of the sender.
• Email servers will verify that the DKIM signature header matches your domain name.
• Unlike SPF, DKIM signature headers will stay with your email even when forwarded.

3) Domain-based Message Authentication, Reporting, and Conformance – DMARC

Finally, the third standard is DMARC, which helps senders make sure that their emails are genuine and trustworthy. This authentication protocol sports features like insights and reporting on authentication failures and suspicious activities. 

• A protocol that uses both SPF and DKIM to determine the authenticity of the email.
• Gives domain owners the ability to protect their domain from unauthorized use.
• Gives instructions to email servers on how to receive the email.
• Protects your brand from spoofing and limits your brand’s and recipients’ exposure to potentially fraudulent and harmful messages.

Check if your DMARC is set up correctly here.

SPF, DKIM, and DMARC are all designed to improve security for email communication, mitigate phishing attacks and spam threats, and protect your business’ reputation. 

Not sure where to start? Be sure to check your deliverability using our downloadable checklist!