Setup checklist#
- ☐ Choose one variable per test and one primary metric (clicks or revenue, not opens).
- ☐ Size samples so results are statistically meaningful; small lists need bigger splits.
- ☐ Run long enough to capture late openers, typically 4 to 24 hours.
- ☐ Log results so learnings persist beyond one campaign.
Audit checklist#
- ☐ Confirm you are not: testing several changes at once.
- ☐ Confirm you are not: declaring winners on open rate after Mail Privacy Protection.
Ongoing monitoring#
- ☐ Weekly: review provider dashboards (Postmaster Tools, SNDS) and bounce logs
- ☐ Monthly: re-run the setup verification after any vendor or DNS change
- ☐ Quarterly: full audit against this checklist
Frequently asked questions#
What should I A/B test first in email?
Subject lines, then the primary call to action, then send time. These have the largest measurable effect.