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Postmark SMTP Setup

Content Plan

This document should cover configuring Postmark for WordPress transactional email delivery.

Planned Content​

TL;DR​

  • Quick setup steps for Postmark + FluentSMTP
  • Key credentials needed: API token, sender signature
  • Verification checklist

Why Use Postmark​

  • Benefits over default WordPress mail (wp_mail)
  • Delivery reliability and inbox placement
  • Transactional vs marketing email distinction
  • When to use Postmark vs other providers (SendGrid, Mailgun, etc.)

Postmark Account Setup​

  1. Creating a Postmark account
  2. Server vs stream configuration
  3. Setting up sender signatures (email verification)
  4. Domain authentication (DKIM, SPF, Return-Path)
  5. DNS records required for domain verification

FluentSMTP Plugin Configuration​

  1. Installing FluentSMTP on WordPress
  2. Selecting Postmark as the mailer
  3. Entering API credentials
  4. Configuring sender (From) address
  5. Setting fallback options

Testing Email Delivery​

  • Using FluentSMTP's test email feature
  • Checking Postmark activity/logs
  • Verifying headers and authentication
  • Common test scenarios (contact forms, password resets, WooCommerce)

DNS Configuration​

Example DNS records for Postmark domain verification:

DKIM:
Type: TXT
Name: {selector}._domainkey
Value: {provided by Postmark}

Return-Path:
Type: CNAME
Name: pm-bounces
Value: pm.mtasv.net

Troubleshooting​

IssueCauseSolution
Emails not sendingInvalid API keyVerify API token in Postmark dashboard
Emails going to spamMissing DKIM/SPFAdd DNS authentication records
Bounce errorsInvalid senderVerify sender signature in Postmark
Rate limitingVolume exceededCheck Postmark plan limits

Client Handoff​

  • What clients need to know about transactional email
  • Monitoring delivery in Postmark dashboard
  • When to escalate delivery issues