Numbers below are illustrative and representative of this engagement type. The subject is anonymized, and every figure sits inside published benchmark ranges.
The situation: 79% of mail reaching the inbox
The publisher ran a daily newsletter and a few weekly sends to all 250,000 subscribers, and treated the full list as the audience. A seed test put inbox placement at 79%, meaning roughly one in five sends never reached a primary inbox. For a business that sells against opens and clicks, that gap pulled directly out of ad revenue.
The cause was volume to people who had stopped reading. Spam complaints sat at 0.22%, above Gmail's 0.10% target though still under the 0.30% hard limit. Mailbox providers read low engagement on a large list as a reputation signal, so every send to dormant addresses dragged placement for the people who did want the mail.
What the audit found: 41k dormant subscribers
About 41,000 subscribers, roughly 16% of the list, had not opened or clicked in months. That tracks with MailPoet's finding that near 30% of an aged list is typically inactive, so this list was actually cleaner than most, yet still heavy enough to suppress placement. None of those addresses were suppressed, and all of them counted against engagement metrics on every send.
Authentication had gaps too. SPF and DKIM were in place, but DMARC monitoring was thin, and the marketing footer carried a mailto unsubscribe rather than the one-click header that the Gmail and Yahoo rules require on bulk mail. Under those Feb 2024 rules, bulk senders need SPF, DKIM, and DMARC, a one-click unsubscribe, and complaints held under 0.30%.
What we built: a 90-day sunset policy
The first move was a sunset policy on Klaviyo's threshold: no open and no click in 90 days routes a subscriber out of the main sends. Before suppression, a short re-permission sequence gave the 41,000 dormant addresses a last chance to opt back in. The few who re-engaged stayed, the rest moved to a suppressed segment that no longer counted against reputation. The full method sits on the deliverability service page.
The compliance work ran in parallel. DMARC reporting moved to active monitoring, the one-click unsubscribe header replaced the mailto-only footer, and complaint tracking was wired into the reporting stack so the team could watch the 0.30% line in real time. Engagement segmentation then split the daily send by recency, so the most active readers anchored the sender's reputation. We track these signals through AI analytics and reporting.
The results: a 16-point lift in inbox placement
Ninety days after the sunset and the compliance fixes, a fresh seed test put inbox placement at 95%, up from 79%. Spam complaints fell to 0.05%, below Gmail's 0.10% target. Click rate rose from 1.9% to 3.4%, because the remaining list was made of people who wanted the mail, and revenue per send climbed 28% even though the list was smaller.
| Metric | Before | After | Change |
|---|---|---|---|
| Inbox placement | 79% | 95% | +16 pts |
| Spam-complaint rate | 0.22% | 0.05% | -0.17 pts |
| Click rate | 1.9% | 3.4% | +1.5 pts |
| Revenue per send | baseline | +28% | +28% |
The headline that surprises publishers is the revenue per send rising while the list shrank by 16%. Mailing fewer people lifted total performance because placement and engagement, not raw list size, set what each send earns. These figures remain illustrative of the engagement, not a guaranteed outcome.
What it means for publishers: a smaller list can earn more
A publisher mailing its whole list to chase reach usually gets the opposite. Dormant addresses drag placement, so the active readers see less of the mail they asked for. The fix is a standing sunset policy plus the Gmail and Yahoo authentication baseline, not a one-time list scrub that drifts back within a quarter.
Across these rebuilds, sender reputation behaves like a budget: spend it on engaged readers and every send earns more. If your placement sits below 90%, the Growth retainer covers this scope, and the other results show how the numbers move by sector.