Glossary
Bulk sender requirements
Also called Google and Yahoo sender requirements, February 2024 email requirements.
Last reviewed 18 September 2026
What are the bulk sender requirements?
The bulk sender requirements are the list Google and Yahoo both began enforcing in February 2024: SPF and DKIM on the sending domain, a DMARC record on the From domain, one-click unsubscribe in the headers, unsubscribe requests honoured within two days, and a spam complaint rate under 0.3 per cent.
Google defines a bulk sender as one sending close to 5,000 messages a day or more to Gmail addresses from the same domain, and applies the stricter items above that line. The authentication floor applies to everyone at any volume: unauthenticated mail is refused rather than filtered, and Gmail returns a 5.7.26 error for it.
The practical reading for a small sender is that the whole list applies anyway. You will cross the bulk line on a good month, none of it is work worth doing reactively, and between them the two providers hold most of the consumer addresses an English-language course is sent to.
See also
- Spam complaint rate
A spam complaint rate is the count of people who pressed the spam or junk button divided by the mail delivered to that provider over a window it chooses, and Google and Yahoo both name 0.3 per cent as the level to stay under and 0.1 per cent as the level to aim at.
- One-click unsubscribe
One-click unsubscribe is a mail client operating the unsubscribe on the reader’s behalf by POSTing to an https URI the sender put in the message headers, with no browser, no confirmation page and no further interaction from the reader, as RFC 8058 defines it.
- DMARC
DMARC is the DNS policy that ties SPF and DKIM to the domain a reader actually sees, telling receivers what to do with mail from your domain that aligns with neither and asking for aggregate reports about it, and it is defined in RFC 7489.
- Deliverability
Deliverability is the share of the mail you send that reaches the inbox of the person you addressed it to, as distinct from delivery, which is only the share the receiving server accepted rather than bounced.
Read next
This term is covered properly in Email deliverability for small senders: authentication and reputation, which is a longer piece on the subject.
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