Deliverability

Gmail and Yahoo sender requirements

Since February 2024, Gmail and Yahoo enforce authentication and unsubscribe rules. Here is the checklist, and how to test your own email against it.

Updated October 1, 2026 · 2 min read

Requirements for everyone

  • SPF or DKIM for your sending domain (SPF checker, DKIM checker).
  • Valid forward and reverse DNS for the sending servers (PTR record).
  • TLS for the connection to Gmail and Yahoo.
  • A spam complaint rate below 0.3%, ideally below 0.1%, as shown in Google Postmaster Tools.
  • Messages formatted according to RFC 5322 (valid headers such as Date, From and Message-ID).
  • No impersonation of Gmail: do not use @gmail.com in the From header of mail sent through other servers.

Additional requirements for bulk senders

  • SPF and DKIM, both set up for your domain.
  • A DMARC record for the From domain, at least p=none (DMARC checker).
  • DMARC alignment: the From domain must match the SPF or the DKIM domain.
  • One-click unsubscribe for marketing mail (RFC 8058): the headers List-Unsubscribe: <https://…> and List-Unsubscribe-Post: List-Unsubscribe=One-Click, plus a visible unsubscribe link. Process unsubscribes within two days.

Checklist

RequirementHow to checkTypical fix
SPFSPF checkerAdd your email service’s include:
DKIM with your domainDKIM checkerEnable domain authentication at your email service
DMARC recordDMARC checkerv=DMARC1; p=none; rua=mailto:…
Reverse DNSSpam checkerPTR record via your hosting provider
One-click unsubscribeSpam checkerEnable List-Unsubscribe in your email tool
Low complaint rateGoogle Postmaster ToolsOnly send to people who opted in; clean your list

Frequently asked questions

Who counts as a bulk sender?

Google defines bulk senders as those sending close to 5,000 or more messages a day to personal Gmail accounts. Once you reach that, you stay a bulk sender. Yahoo applies similar rules without publishing an exact number.

What happens if I do not meet the requirements?

Messages are increasingly rejected or delivered to spam. Google returns errors that link to its sender guidelines.

How do I check my email against these requirements?

Send a message to the email spam checker. It shows SPF, DKIM, DMARC, reverse DNS, List-Unsubscribe and the SpamAssassin score in one report.

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GET https://api.emailvalidation.io/v1/info?email=support@emailvalidation.io

{
  "email": "support@emailvalidation.io",
  "domain": "emailvalidation.io",
  "format_valid": true,
  "mx_found": true,
  "smtp_check": true,
  "disposable": false,
  "role": true,
  "free": false,
  "score": 0.64,
  "state": "deliverable",
  "reason": "valid_mailbox"
}

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