Gmail, Yahoo and Microsoft bulk sender rules
If you send about 5,000 or more emails a day to Gmail, Yahoo or Microsoft consumer inboxes, all three now require email authentication. Mail that doesn't comply is pushed to spam or rejected outright.
Check your domain against these rules
The checklist
| Requirement | Gmail | Yahoo | Microsoft |
|---|---|---|---|
| SPF for your sending domain | Yes | Yes | Yes |
| DKIM signature | Yes | Yes | Yes |
DMARC, at least p=none | Yes | Yes | Yes |
| From domain aligned with SPF or DKIM | Yes | Yes | Yes |
| Valid forward and reverse DNS (PTR) on sending IPs | Yes | Yes | Recommended |
| One-click unsubscribe on marketing mail | Yes | Yes, honoured within 2 days | Clear unsubscribe expected |
| Low spam complaints | Under 0.3% (aim under 0.1%) | Under 0.3% | Keep lists clean |
| TLS encryption when sending | Yes | Recommended | Recommended |
Key dates
- February 2024: Gmail and Yahoo begin enforcing their bulk-sender rules.
- June 2024: one-click unsubscribe deadline for marketing mail.
- 5 May 2025: Microsoft starts rejecting non-compliant bulk mail to Outlook.com, Hotmail.com and Live.com with error
550 5.7.15 Access denied. - November 2025: Google steps up enforcement on non-compliant traffic.
What to do this week
- Run the checker and fix any red items. It gives you the exact records.
- Turn on DKIM in every tool that sends as your domain, not just your mailbox provider.
- Publish DMARC at
p=nonewith a report address, then work towardsp=quarantineorp=reject. The DMARC generator builds the record. - Make sure your newsletter tool adds one-click unsubscribe headers, and remove addresses that bounce.
- Watch your spam rate in Google Postmaster Tools.
Sources
- Google: Email sender guidelines
- Yahoo Sender Hub: best practices
- dmarcian: Microsoft enforces SPF, DKIM and DMARC
- dmarcian: Yahoo and Google require DMARC
Checked 2026-10-29. Providers change their rules; follow the sources above for the latest wording.