Google will automatically block emails sent by bulk senders who don’t meet stricter spam thresholds and authenticate their messages. Bulk email senders must avoid sending unsolicited or unwanted messages, provide an unsubscribe option, and respond to unsubscription requests within two days. Spam rates must be maintained below 0.3%, and “From” headers must not impersonate Gmail. Non-compliance may result in email delivery issues, including rejected emails or emails being sent to recipients’ spam folders. Google plans to enforce these requirements starting in June, with an accelerated timetable for domains used to send bulk emails since January 1, 2024.