Setup checklist#
- ☐ Keep subject lines under 50 characters so they survive mobile truncation.
- ☐ Write the preheader as a continuation, not a repeat of the subject.
- ☐ A/B test one variable at a time with a statistically meaningful sample.
- ☐ Avoid deceptive 'Re:' or 'Fwd:' prefixes, which violate CAN-SPAM and raise complaints.
Audit checklist#
- ☐ Confirm you are not: clickbait that produces opens but drives complaints and unsubscribes.
- ☐ Confirm you are not: all-caps and excessive punctuation, which pattern-match to spam.
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#
Do emojis in subject lines hurt deliverability?
Not directly. They can hurt engagement with B2B audiences and render inconsistently across clients.