Enterprise deliverability meets developer control
While Postmark built its reputation on reliable transactional email, its newer role under ActiveCampaign adds complexity and blurred pricing for developers. Mailgun delivers the same trusted inbox reach – with deeper deliverability tooling, open APIs, and freedom from marketing lock-ins.
Why Sinch Mailgun?
Advanced deliverability and inbox placement testing
HIPAA, SOC 2, GDPR, and CCPA compliance
Transparent pricing with free tier (100 emails/day)
Dedicated IPs and full event logging
Developer-first REST API and SDKs in 5+ languages
START FAST, SCALE CONFIDENTLY
Postmark is strong for simple transactional sends – password resets, receipts, notifications – but scaling often means hitting walls on event retention, reporting, and pricing tiers tied to ActiveCampaign’s marketing suite. Mailgun is purpose-built for technical teams who need flexibility, transparency, and control.
BUILT FOR DELIVERABILITY, NOT JUST DELIVERY
Deliverability isn’t just about getting through SMTP. It’s about staying off blocklists, optimizing warm-up, and understanding why an email missed the inbox.
Postmark focuses on reliability but doesn’t match Mailgun’s data visibility or deliverability engineering support.
Mailgun’s Optimize suite includes:
Inbox placement testing across major ISPs
Spam trap and blocklist monitoring
Email validation (single, bulk, and list health previews)
Bounce classification and reputation reporting
EMAIL EXPERTS AT YOUR SERVICE
Mailgun customers work directly with seasoned deliverability engineers, not generalist support.
Postmark offers responsive email-based support, but not Mailgun’s enterprise-grade SLAs or deliverability consulting.
Mailgun support advantages:
24/7 chat and ticket support
SLAs available on Scale & Enterprise plans
320+ years of combined deliverability experience
Dedicated onboarding & migration guidance
More Control And Flexiblity
Mailgun’s open APIs, flexible SDKs, and data transparency give engineering teams more power over their email infrastructure.
Compliance and Security
Mailgun’s compliance and data-protection frameworks are designed for regulated industries like healthcare, fintech, and SaaS. Postmark’s security stance is solid, but Mailgun goes further with regional data routing and enterprise identity integrations.
Product Reviews & Ratings
For us, at the volume we’re sending – every fraction of a percentage means a potential customer, and as a community of designers, it’s our job to create meaningful touchpoints. High deliverability ensures that our messages and our reach are seen; any improvement in our email program has a huge effect on our business.
Mailgun has great ability in email delivery. It’s also really reliable as I have not heard my website users complaining about not receiving emails. The sort of new intuitive design makes me like Mailgun even more!
Pricing Comparison
Mailgun customers report up to a 50% reduction in total sending cost after switching due to better deliverability, fewer add-ons, and no forced marketing suite overhead.
Use Cases
Advanced deliverability monitoring
HIPAA-ready compliance
Scalable sending from 100k to millions/month
Global data residency (US + EU)
24/7 support and onboarding help
Use Cases
Simple transactional email for small apps
Clean API for basic notifications
1:1 developer integrations with limited compliance needs
Short-term volume for simple use cases
Migration Checklist
Switching from Postmark to Mailgun is simple with guided support and developer-ready docs.
Migration Checklist:
Step 1: Export Postmark templates and map to Mailgun’s Handlebars/MJML templates
Step 2: Update DNS (SPF, DKIM, DMARC)
Step 3: Recreate event webhooks (deliveries, bounces, opens
Step 4: Validate list health and sender reputation
Step 5: Gradually warm up IPs for new sending domain
FAQs
Postmark focuses on lightweight transactional sending, while Mailgun adds advanced deliverability, analytics, and compliance for production-scale email programs.
Yes – 100 emails/day forever. Postmark’s free plan includes 100 emails/month.
Yes. Mailgun supports HIPAA, SOC 2, GDPR, and CCPA compliance.
Mailgun provides documentation and support for setup, DNS verification, and IP warm-up.
Mailgun powers transactional and API-based sending, while Mailjet (also part of Sinch Email) handles marketing campaigns.
Mailgun has a variety of features for companies with large lists and bulk sending needs.
More than just sending email
Email deliverability services
Email deliverability experts
Blocklist monitoring service
Ensure every email hits the inbox
Email deliverability
Email list management
Email analytics
Read how other companies are using Mailgun
Email testing tool
Check sender reputation
Email reputation check
Published November 2025