Email deliverability checklist for 2026 (the 12 things that matter)

Short answer: the 2026 fundamentals are authentication (SPF + DKIM + DMARC), a warmed domain, bounce rate under 2.5%, a low spam-complaint rate, one-click unsubscribe (Gmail and Yahoo now effectively demand it from bulk senders), and steady volume. Nail those and most cold mail reaches the inbox. Miss one and placement falls apart.

The 12-point checklist

1. SPF record published and passing.
2. DKIM signing on every send.
3. DMARC policy (at least p=none with reporting; move to quarantine).
4. Custom tracking domain (not a shared one).
5. Warmed mailbox (21+ days) before cold sends.
6. Bounce rate < 2.5% — verify lists first.
7. Spam complaints < 0.1%.
8. One-click unsubscribe header (List-Unsubscribe-Post).
9. Plain, personal copy — no spammy formatting.
10. Per-mailbox daily caps + rotation.
11. Engagement — prune non-openers, prioritise repliers.
12. Monitor reputation (Google Postmaster / placement tests).

Autocloz runs 1–12 for you — auth checks, warmup, caps, one-click unsubscribe, and bounce auto-pause.

> Start free — run the whole checklist on autopilot.