Postmark vs Substack
Pricing
Postmark: Free for 100 emails/mo, from $15/mo
Substack: Free, 10% of paid subs
Description
Postmark: Transactional email service built around one promise: your emails hit the inbox
Substack: The OG paid newsletter platform
Pros
- Industry-leading deliverability: 99%+ inbox placement
- Emails typically arrive in under 10 seconds
- Detailed delivery analytics and debugging tools
- Built-in audience discovery
- No upfront costs
- Simple and focused
Cons
- More expensive per email than Resend or SendGrid
- Transactional email only: no marketing campaigns, newsletters, or bulk sends
- 100 email free tier is barely enough to test with
- 10% cut is steep at scale
- Limited customization
Details
Postmark has been laser-focused on one thing for over a decade: making sure transactional emails hit inboxes, not spam folders. Password resets, order confirmations, shipping notifications: the emails your users actually need to receive. They keep their deliverability high by refusing to send marketing email on the same infrastructure.
You pay more per email than alternatives, but for transactional messages where delivery matters (think: password resets, payment receipts), that premium buys real reliability. If your app sends emails that users rely on, Postmark is the safest bet.
Substack pioneered the paid newsletter model. Founded by Chris Best and Hamish McKenzie in 2017. Free to start, they take 10% of paid subscriptions. Over 5M paid subscriptions on the platform. Great for writers who want zero setup friction.
Verified
