Postmark

Postmark deliberately limits itself to transactional email. Streams keep transactional and broadcast traffic separated. The product emphasizes message activity retention, clear debugging, and volume pricing with no feature gates.

At an early stage the deciding factors are what the free tier actually covers, what the first paid invoice looks like, and how much of a founding engineer's week the setup costs. Feature depth that only matters at a million sends a month is noise until it is not.

Against a waitlist, a launch announcement, onboarding email, and the first transactional sends, Postmark covers developer experience, SDK breadth, and webhook coverage, and does not cover best published rate per 1,000, operating track record, and scheduling. Whether that gap matters depends on how central those are to the build.

• Free tier: 100/mo developer plan
• Best published rate per 1,000: $1.50
• Starts at: $15/mo for 10,000 emails
• DX score: 9/10
• Deliverability: Strong transactional reputation with separate streams for transactional and broadcast traffic, which helps protect sender reputation.
• Operating since: 2010
• Scheduling: No
• SDKs: node, python, go, ruby, php, java, elixir, rust, dotnet
• Webhooks: Yes

Strong transactional reputation with separate streams for transactional and broadcast traffic, which helps protect sender reputation.

Teams where password resets, receipts, and magic links absolutely cannot miss the inbox.

Marketing automation, abandoned-cart sequences, lifecycle nurturing.