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Reverse DNS (PTR) records checklist for 2026

Short answer

A complete reverse DNS (PTR) records checklist has 4 setup items and 2 things to audit against. Work through setup in order, then schedule a quarterly review.

Setup checklist#

  • ☐ Ask your hosting or ESP provider to set a PTR for each sending IP.
  • ☐ Use a hostname under your domain (mail1.example.com) rather than the provider's generic name.
  • ☐ Create the matching A record so forward and reverse agree.
  • ☐ Use the same hostname in the SMTP HELO/EHLO banner.

Audit checklist#

  • ☐ Confirm you are not: generic PTRs like 203-0-113-10.provider.net.
  • ☐ Confirm you are not: hELO names that do not match the PTR.

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#

Can I set PTR records in my own DNS?

No. PTRs live in the IP owner's reverse zone. Your hosting provider or ESP sets them, though some offer self-service.

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