Yahoo Mail SMTP settings: smtp.mail.yahoo.com, port 465 or 587

Yahoo Mail outgoing server: smtp.mail.yahoo.com, port 465 SSL or 587 STARTTLS, full Yahoo address and a generated app password. Limits (about 500 a day, 100 recipients per message) and error fixes.

Yahoo Mail outgoing mail server: smtp.mail.yahoo.com, port <code>465</code> (SSL/TLS) or <code>587</code> (STARTTLS), username = your full Yahoo address, password = an app password generated in Yahoo account security.

Yahoo Mail SMTP settings at a glance

Outgoing (SMTP) hostsmtp.mail.yahoo.com
Ports & encryption
465 — SSL/TLS <em>(recommended)</em>
587 — STARTTLS
Usernameyour full Yahoo address, e.g. you@yahoo.com
Passwordan app password generated in Yahoo account security (normal passwords are refused by third-party apps)
AuthenticationYahoo requires "Generate app password" for any app that is not Yahoo's own: Account Info → Account Security → Generate app password. Third-party apps with the account password get 535.

How to set up Yahoo Mail SMTP

  1. Sign in → Account Info → Account Security → turn on two-step verification if asked → "Generate app password", pick "Other app", copy the password.
  2. App settings: host smtp.mail.yahoo.com, port 465 with SSL/TLS (or 587 STARTTLS), username = full address, password = the app password.
  3. Send a test; if it bounces as 554 "Message not allowed", the From address is not your Yahoo address.

Sending limits

  • About 500 messages per day and 100 recipients per message; Yahoo lowers this for new or flagged accounts.
  • From must be the Yahoo address (or a verified extra address).

Things that catch people out

  • Yahoo's DMARC policy is p=reject: mail claiming a @yahoo.com From that does not go through Yahoo's servers is rejected by every major inbox — never send "from" a Yahoo address through another SMTP server.

Common Yahoo Mail SMTP errors

Server replyMeaningFix
535 5.7.0 (#AUTH005) Too many bad auth attemptsRepeated logins with a wrong or non-app password.Wait, then use a fresh app password.
554 5.7.9 Message not accepted for policy reasonsContent or From-address policy.Send from the Yahoo address; avoid bulk-looking mail.
421 4.7.0 Temporary errorRate limit.Slow down.

More codes: 535 authentication failed, 550 relay denied, 554 rejected as spam, connection timed out — or all SMTP error codes.

When Yahoo Mail is not enough for your app

When a provider caps you or blocks a port, point the same app at QueenSMTP instead: host smtp.queensmtp.com, port 587 (STARTTLS) or 465 (SSL), your SMTP username and password from the dashboard. $5/year plus $0.10 per 1,000 emails, 100 free a day to test.

Get SMTP credentials — free to test Test Yahoo Mail now

Verified 2026-08-30 against Yahoo Mail's documentation and live DNS. Found a change? Tell us.

Yahoo Mail SMTP — questions

smtp.mail.yahoo.com, port 465 with SSL (or 587 with STARTTLS). Username is your full Yahoo address; the password must be an app password.

Yes, with an app password, but only sending as your Yahoo address and within roughly 500 messages a day. Yahoo's strict DMARC means the From address cannot be your own domain.