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Postmark

API100 free test emails

Premium transactional email service focused on speed and reliability.

Best For
Business-critical transactional emails where speed and reliability matter
Pricing
10,000 emails for $15/month, scales with volume
Integration Type
API

Overview

Postmark is a premium transactional email service that focuses exclusively on delivery speed and reliability. Unlike multi-purpose platforms, Postmark is built from the ground up for transactional emails, resulting in industry-leading delivery times (often under 10 seconds).

Postmark's strict anti-spam policies mean exceptional deliverability, making it ideal for critical emails like password resets and order confirmations.

Postmark Features

Fastest delivery times in industry
Dedicated to transactional email only
Message streams for organization
Dedicated IP addresses
Templates with variables
Webhook support
Excellent customer support
45-day message retention
Bounce handling
DMARC weekly reports

Requirements

Before you start, make sure you have:

  • 1Postmark account
  • 2Server API token
  • 3Verified sender signature

Step-by-Step Setup Guide

1

Create a Postmark Account

1. Go to postmarkapp.com and click "Start Free Trial"

2. Enter your details and create an account

3. Verify your email address

4. You'll start with 100 free test emails

2

Create a Server

1. In Postmark, go to Servers

2. Click "Add Server"

3. Name it (e.g., "WordPress Site")

4. Set the server type to "Live" for production

5. Note your Server API Token

3

Add Sender Signature

1. Go to your server → Sender Signatures

2. Click "Add Signature"

3. Choose "Sender Address" for quick start

4. Enter your email address

5. Confirm via the verification email


For better deliverability, add a Domain signature instead.

4

Configure Authority Mailer SMTP

1. In WordPress, go to Authority Mailer SMTP → Settings

2. Select "Postmark" from the provider dropdown

3. Paste your Server API Token

4. Set your "From Email" (must be verified signature)

5. Set your "From Name"

6. Save and send a test email

💡 Pro Tips

  • Postmark is overkill for marketing emails - use for transactional only
  • Use message streams to separate transactional types
  • Enable DMARC reports for delivery insights
  • Postmark's support is exceptional - don't hesitate to contact them
  • Monitor bounce rates to maintain reputation

🔧 Troubleshooting

❓ API returns 401 error

✅ You're using the wrong token. Use the "Server API Token", not the "Account API Token".

❓ Sender signature not found

✅ The From email must match a verified signature. Add and verify it in Postmark.

❓ Account still in test mode

✅ Complete account verification and payment setup to move to production.

❓ Message stream errors

✅ Authority Mailer SMTP uses the default transactional stream. Contact support if you need custom streams.

Ready to Set Up Postmark?

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