A quarterly ranking of how brands treat the inbox they were invited into. Every figure comes from email a Siftbox panel inbox actually received, never from scraping a website, and every claim traces to a specific message with its date and subject line. The grade is the Siftbox Score, out of 12.
The quarter has not closed, so the figures below are provisional and will change: the panel keeps receiving mail every day, and scores, bands and rankings all move with it. They are published early to show the method, not the result. The final Q3 2026 editions publish on Oct 1.
43 brands scored on Restraint, Urgency and Sale permanence.
Read the edition →27 newsletters scored on Cadence, Volume and Sales pressure.
Read the edition →Four bands, one question: when this brand hits send, what is it putting first?
Siftbox sells a solution to the problem this index measures.
That sentence leads the methodology on purpose. The index is free, brands are never contacted before publication, and no brand is ever offered a way to change a score.
The panel. Siftbox operates a panel of subscriber inboxes that sign up to brand newsletters the way any customer would: an email form on the brand's own site, no account created, no terms assented to. Brands requiring a registered account are excluded.
The Siftbox Score. Three dimensions per edition, 0 to 4 each, out of 12, permanently. Always written with its scale. Scores compare within an edition, not across editions: the two editions measure different dimensions on the same scale. Past editions are never restated.
Auditable where it cannot be reproducible. Nobody can re-check a send rate without their own panel, so each edition publishes its receipts: counts, dates and subject lines beside the scores.