Two transactional email providers, compared on price, features and ratings, so you can pick fast.
OneSignal Email wins deliverability and compliancePostmark wins developer experience and cost at scale
Updated July 2026
At a glanceOneSignal EmailPostmark
Entry priceFree$10
Cost per 1k @ 100k$1.39$1.26
Free tier10,000/mo100/mo
G2 rating4.74.6
THE VERDICT
OneSignal Email wins on deliverability and compliance. Postmark wins on developer experience and cost at scale.
OneSignal Email starts at Free versus Postmark's $10. OneSignal Email rates higher with developers (4.7 vs 4.6 on G2). Pick based on volume and team, and the scorecard below breaks down where each one leads.
Which should you choose?
Pick OneSignal Email
✓If you're looking to send push notifications to people who use your website, OneSignalEmail is a great option for you.
✓It is an excellent choice if you or your brand have an audience spread across various platforms and manage them efficiently.
Winner cells are tinted, green where OneSignal Email leads, violet where Postmark does.
capability
OneSignal Email
Postmark
Pricing
Starting paid plan
$19/mo
$15/mo
Cost per 1k @ 100k
$1.39
$1.26
Pricing model
Hybrid
Subscription
Overage
$1.50 / 1,000 sends
$1.20–$1.80 per 1,000 by plan
Deliverability
Dedicated IP
Plan-gated
Add-on
Deliverability tooling
Yes
Yes
Automated IP warmup
Yes
No
Suppression management
Yes
Yes
SPF / DKIM / DMARC
Yes
Yes
API & sending
Transactional API
Yes
Yes
Marketing campaigns
Yes
No
SMTP relay
—
Yes
Inbound routing
—
Yes
Dynamic templates
Yes
Yes
Batch send
Yes
Yes
Scheduled send
Yes
No
Developer experience
Official SDKs
Node.js, Python, Java, Go, PHP, Ruby, C#, Rust
.NET, Java, Node.js, PHP, Python, Ruby, Rails
Event webhooks
Yes
Yes
Drag-and-drop editor
Yes
No
Custom HTML editor
Yes
Yes
Email validation
—
No
Log retention
—
45 days
Sandbox / test mode
—
Yes
Analytics
Open / click tracking
Yes
Yes
Analytics dashboard
Yes
Yes
A/B testing
Yes
No
Compliance
EU data residency
—
No
SOC 2
Yes
No
HIPAA
BAA
No
GDPR
Yes
Yes
ISO 27001
Yes
No
Support
Support channels
Email, Community
Email, Chat
24/7 support
Yes
No
Support SLA
Plan-gated
No
FAQ
Common questions
OneSignal Email starts at Free versus Postmark's $10. Because pricing models differ by tier, the cheaper option depends on your monthly volume, so compare the pricing rows in the scorecard above.
Pricing, plans and feature availability as of July 2026 and may change. Ratings are aggregated from public review platforms. Postmark is an ActiveCampaign product.