80
Stack Score
Editorial pick✓ Verified working
Postmark
Reliable transactional email API for developers.
Try Postmark✓ Free trial available
Best for
Engineering teams who want best-in-class transactional deliverability and fast support.
At a glance
- Pricing
- paidfrom $15/mo
- Setup time
- 30 minutes
- Learning curve
- easy
- Last verified
- 5/22/2026
What we love
- ✓Industry-leading transactional deliverability
- ✓Excellent docs and support
- ✓No marketing-spam risk to your domain
Where it falls short
- −No marketing tools
- −Pricier per-1K than SendGrid
- −No SMS
Pricing
✓ Pricing verified Jun 21, 20264 tiers
Free Trial
100 emails
30 days
- ✓Full feature access
Starter
$15
per month
- ✓10K emails/mo
$1.25 per 1K
$1.25
per 1K emails (50K-2M)
- ✓Up to 2M
Volume
Custom
quote
- ✓High-volume rates
Why we picked it
Postmark is what you reach for when transactional email absolutely has to land. SendGrid lost the deliverability crown years ago.
Overview
Reliable transactional email API for developers. Engineering teams who want best-in-class transactional deliverability and fast support.
Key features
- ●Separate streams for tx and broadcast
- ●Fast delivery (sub-10s p95)
- ●Bounce + spam handling
- ●Templates + MJML
- ●Inbound parsing
- ●Real-time activity log
- ●Strong DMARC tooling
Best use cases
Password resets and receipts
Critical transactional that must arrive.
Inbound email parsing
Build email-as-an-API features.
Integrations
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