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How to Send Yahoo Mail From Gmail After January 2027

Updated 2026-10-03 · by Adam Hale

To send Yahoo mail from Gmail after January 2027, the message has to go out through Yahoo's own SMTP server (smtp.mail.yahoo.com) using a Yahoo app password. Gmail's "Send as" for third-party addresses ends that month, and Yahoo's DMARC policy stops any other server from sending as @yahoo.com. The same applies to AOL and AT&T addresses.

Why only Yahoo's own server can send as @yahoo.com

Domains publish a DMARC policy that tells receiving servers what to do with mail that claims to be from them but wasn't authenticated by them. When we checked on 2026-10-03:

Domain DMARC policy What it means
yahoo.com, aol.com p=reject Unauthenticated mail claiming these addresses should be rejected
att.net p=quarantine Such mail should go to spam

So a free relay such as Brevo or SMTP2GO cannot send as your Yahoo address. You can verify a custom domain with those services, but not yahoo.com. Every working option below ends with Yahoo's (or AOL's, or AT&T's) server sending the message.

Send Yahoo mail from Gmail: your options

Option Where you write Cost Trade-off
SendAs Relay extension Gmail web, desktop Free for 1 address Firefox and Edge only
MailBridge Send As extension Gmail web, desktop Price not published; early access since 2026-08-05 Its servers hold your SMTP credentials
Gmail app, Yahoo added as a separate account Phone Free Separate inbox; Google says this keeps working
Thunderbird Desktop app Free Leaves Gmail's interface
Yahoo Mail web or app Browser or phone Free Separate place to check

Google's own recommendations are the provider's website or app, a desktop client, or the Gmail mobile app (Gmail Help 17101213).

Step 1: create a Yahoo app password

Yahoo requires an app password for any non-Yahoo app that doesn't use Yahoo's sign-in page (Yahoo Help SLN15241):

  1. Sign in to your Yahoo Account Security page.
  2. Under "External connections", click Create app password.
  3. Enter a name (for example "Gmail sending") and click Generate password.
  4. Copy the password into your app and click Done.

Yahoo warns that eligibility can be refused: "use a browser that you've used to sign into Yahoo for several days in a row and avoid using Incognito mode... Customer care can't override this process." App passwords stay valid when you change your main password; delete them to revoke them.

AOL works the same way (AOL Help). AT&T calls it a "secure mail key": a 16-character code you create for each AT&T address in your account profile (AT&T KM1240308, updated 2026-02-23).

Step 2: use the right SMTP settings

Provider SMTP server Port and security Username Password
Yahoo smtp.mail.yahoo.com 465 SSL/TLS, or 587 Full Yahoo address Yahoo app password
AOL smtp.aol.com 465 SSL/TLS Full AOL address AOL app password
AT&T (att.net, sbcglobal.net, bellsouth.net and others) smtp.mail.att.net 465 or 587, SSL Full AT&T address Secure mail key

Sources: Yahoo IMAP/SMTP settings, AOL POP/IMAP settings, AT&T server settings. More providers are in the SMTP app password table.

Step 3: plan for incoming mail

This is where Yahoo users get caught. Google recommends auto-forwarding as the replacement for POP fetch, but:

So for free Yahoo or AOL accounts, your realistic choices for incoming mail are:

See the POP3 alternative guide for the full comparison.

The credential question

Google cautions that third-party Send-as tools "often require access to your email credentials or OAuth tokens". For Yahoo there's no way around it: whatever sends as @yahoo.com must log in to Yahoo's server. An app password limits the damage: it is separate from your main password, and you can delete it at any time without changing your main password.

How SendAs Relay fits

SendAs Relay is a Firefox (140+) and Edge (137+) extension that adds a From picker to Gmail on the web. Pick your Yahoo, AOL or AT&T address, click Send, and the message goes out through that provider's SMTP server via a small stateless relay. Gmail does not send it.

Not the right fit if Yahoo won't issue you an app password, you mostly write from your phone, or you use Chrome. In those cases the Gmail app or Thunderbird is simpler. See how it works and pricing.

Sources