Gmail and Yahoo sender requirements
What bulk senders must do to keep reaching Gmail and Yahoo, which requirements Mailfully satisfies for you, and which are yours.
Google's bulk-sender rules apply once you send about 5,000 messages a day to personal Gmail addresses. Yahoo applies similar rules without publishing a number. Meet the authentication requirements at any volume.
The requirements below reflect Google's and Yahoo's published sender guidelines as of September 2026.
The requirements
| Requirement | Who satisfies it | What you do |
|---|---|---|
| SPF and DKIM authentication | Mailfully, once your domain is verified | Verify your domain |
| A published DMARC record on the sending domain | You | Publish the _dmarc TXT record Mailfully returns |
Alignment between the DKIM/SPF domains and the from domain | Mailfully | Nothing beyond verifying the domain |
| One-click unsubscribe on marketing mail | Mailfully, when you send with type: "marketing" | Send marketing mail with type: "marketing" |
Spam-complaint rate under 0.3% (0.003) | You | Watch the rate and act before it climbs; see the two ceilings |
What Mailfully already handles
Mailfully signs your outgoing mail with the keys behind the three CNAMEs it returns, once your domain verifies. It provisions the MAIL FROM subdomain and its SPF record as part of adding a domain, and both sit beneath the same sending domain DKIM signs for, which is what lets DKIM and SPF align with the from domain.
On any type: "marketing" send it also adds List-Unsubscribe and List-Unsubscribe-Post headers. The unsubscribe URL in them identifies exactly the one recipient the send goes to.
What is yours
- Publishing the DMARC record.
- Declaring each message's
typecorrectly, so marketing traffic is identified as such. - Honoring opt-outs, and keeping a visible unsubscribe link in the message body; see Policies for the full compliance requirements.
- Keeping your complaint rate under the ceiling above.
Check your complaint rate
GET /v1/analytics/external-reputation reports the same Gmail spam-rate signal these requirements are measured against. See Analytics.
Microsoft and Outlook
Microsoft requires SPF, DKIM, and DMARC to pass for domains sending more than 5,000 messages a day to Outlook.com, Hotmail, and Live.com addresses, effective May 5, 2025. See Microsoft's sender policies for its current guidance, which is the authority for anything beyond that.