Google's sender guidelines say to keep the user-reported spam rate in Postmaster Tools below 0.10% and avoid ever reaching 0.30% or higher. The bulk sender requirements list 0.30% as the line to stay under. Treat 0.10% as your working target.
Definition
The spam rate is the share of your mail that recipients mark as spam, as reported in Google's Postmaster Tools for your domain. It reflects human feedback, not content filters. That makes it a measure of whether people wanted the mail.
Google says a low spam rate makes senders more resilient to occasional spikes in user feedback, and that a high rate leads to more spam classification. It also says improvement can take time to show up after you fix the cause.
Who it applies to
Google's formal requirements apply to senders of more than 5,000 messages per day to Gmail accounts, and the page also lists baseline guidance for all senders. If you are below that volume, the rate still matters for delivery, so use the same target.
What pushes the rate up
Google's guidance names the usual causes:
- Sending to people who did not sign up, or to purchased lists.
- Opt-in forms checked by default.
- No easy unsubscribe, so recipients use the spam button instead.
- Mixing content types, or using misleading subject lines and display names.
- Sudden volume increases, which give recipients more chances to complain before your reputation has built.
Marketing and subscribed messages from bulk senders must support one-click unsubscribe, and the message body should include a visible unsubscribe link. Making leaving easy is the cheapest spam rate control there is. See how one-click unsubscribe works.
A response plan
| Spam rate trend | Action |
|---|---|
| Under 0.10% | Keep monitoring weekly |
| Rising toward 0.10% | Pause the newest segment, check sign-up source and frequency |
| Near 0.30% | Stop non-essential marketing sends, review list sources, confirm unsubscribe works |
| After a fix | Resume at lower volume to engaged recipients and ramp gradually |
Send at a steady rate rather than in bursts, and start new campaigns with engaged users.
Steps
- Register your sending domains in Postmaster Tools.
- Record spam rate and domain reputation per stream, not just overall.
- Alert on a rising trend, not only on a threshold.
- Remove unengaged recipients on a schedule.
- Confirm sign-up forms do not pre-check consent boxes.
- Keep transactional mail on its own identity so a bad marketing week does not touch it. See separating email streams.
Where Safeguard fits
Safeguard's compliance and evidence automation helps you keep records of sending domains, authentication settings and policy checks in one place. The free scan is at https://gold.safeguard.sh/scan.
Quick check
Is 0.30% the goal?
No. It is the line to stay under. Google recommends keeping the rate below 0.10%.
Does spam rate include filtered mail?
The Postmaster Tools figure reflects user spam reports, so it shows how recipients react rather than what filters caught.
Sources
Last reviewed: 19 October 2026.
