Resend is the right email API for most developer teams in 2026, starting free at 3,000 emails per month and charging $0.90 per 1,000 extra on its $20/month Pro plan. Postmark has a longer deliverability track record and a searchable 45-day message log, but its overage rate of $1.80 per 1,000 emails on the base plan makes it harder to justify unless inbox placement is your primary concern.
Our Top Pick
All Options Compared
| Feature | Resend | Postmark |
|---|---|---|
| Free tier | Free available | Free available |
| Paid price | $20.00 USD/mo | $15.00 USD/mo |
| React Email Support | — | |
| Transactional Email | ||
| Marketing Email | — | |
| Webhooks | ||
| Custom Domains | — | |
| Dedicated I Ps | Scale plan only | Paid add-on |
| Sdk Languages | 8 official SDKs | — |
| Mcp Server | — | |
| Open Tracking | — | |
| Click Tracking | — | |
| Bulk Email | — | |
| Inbound Processing | — | Pro+ only |
| Message Streams | — | |
| Templates | — | |
| Data Retention | — | 45-365 days |
| Smtp Support | — | |
| Rest Api | — | |
| Score | 8/10 | 8/10 |
1. Resend — Best Overall
Resend launched in 2023 and has moved fast. The API takes about five lines of code to send an email in any of its eight official SDKs, which cover Node, Python, Ruby, Go, PHP, Rust, Elixir, and more. The free plan gives you 3,000 emails per month with a 100-per-day cap, which is enough to carry you through development and light production use without a credit card.
The standout feature is React Email integration. Because Resend and React Email come from the same team, writing email templates as React components and rendering them to HTML before sending is completely native to the workflow. If you already build in React, this removes the entire problem of maintaining HTML email templates.
The Pro plan at $20 per month includes 50,000 emails and webhooks. Overages run $0.90 per 1,000, which is competitive. The Scale plan starts at $90 per month for 100,000 emails and adds dedicated IP options. Where Resend is thinner is analytics: you get open rates and click tracking, but no click maps or engagement timelines. It also has no phone support at any tier.
Resend is also newer than Postmark by about a decade, which is a real consideration for organizations that need an established vendor. But for startups and developer-led teams, the clean API, React Email support, and generous free tier make it the clear starting point.
2. Postmark — Best for Transactional Deliverability
Postmark has been focused on transactional email since 2009 and that focus shows. It uses separate IP pools for transactional and broadcast mail, which means your password reset emails never share reputation with a newsletter campaign. Median delivery time in independent tests comes in around 10 seconds, consistently near the top of what the field offers.
The Message Activity feature is a genuine debugging tool: a searchable 45-day log with full content previews. When an email is not arriving, you can look up exactly what was sent, when it was received by the server, and why it may have bounced. That kind of visibility is worth a lot on a product where email failures cause support tickets.
The free Developer tier gives you 100 emails per month, which is only useful for testing an integration. Paid plans start at $15 per month for 10,000 emails, with overages at $1.80 per 1,000 on Starter or $1.30 per 1,000 on the Growth plan ($16.50 per month). Growth also adds inbound email processing and up to 365-day data retention. One thing to note: ActiveCampaign acquired Postmark in 2022, and the product has taken on some enterprise-facing complexity since then.
Postmark does not support marketing or bulk email at all, by design. If you need both transactional and broadcast in one tool, it does not fit.
How We Ranked These
We ranked these by overall value for a typical developer team: free tier usability, cost per email at moderate volume, SDK breadth, and how much the API gets out of the way. Deliverability and debugging tooling were secondary factors, weighted higher for teams where email reliability directly affects user experience.