Honest Review: Resend vs SendGrid vs Postmark

I've shipped transactional email through Resend, SendGrid, and Postmark in the last 18 months. They are not equivalent. The right pick depends on your project's shape.

What each is good at

Resend is the developer-first newcomer. Clean API, React Email integration, batch sends, scheduling. Modern UX. Built by people who actually use it.

SendGrid is the enterprise default. Mature, broad feature set, comprehensive analytics. Used by everyone from solo founders to Fortune 500.

Postmark is the deliverability-first option. Famously reliable inbox placement. Strict on what they let through to protect the sender pool.

Where Resend wins

Developer experience. The API is the cleanest of the three. The docs are the best. The integration with React Email is the killer feature for any team using React.

Modern features. Batch sending, scheduled sends, audience management, broadcast emails. They're shipping fast and the features are good.

Pricing transparency. The pricing is simple and reasonable for most use cases.

Where SendGrid wins

Enterprise depth. SSO, advanced analytics, comprehensive A/B testing, sophisticated automation tools. If your needs are deep, SendGrid has been doing this longer.

Reliability at scale. SendGrid handles billions of emails. The infrastructure is mature. At very high volumes, this matters.

Integrations. Everything integrates with SendGrid. If you're connecting to lots of marketing tools or analytics systems, SendGrid usually has a path.

Where Postmark wins

Deliverability. Postmark is famous for inbox placement. They strict about sender reputation and won't take spammy senders. Your transactional email reaches inboxes.

Transactional focus. Postmark is built specifically for transactional email (receipts, password resets, magic links). Their architecture optimizes for those use cases.

Honesty in marketing. Postmark publishes their actual delivery times and rates. Refreshingly transparent.

When to pick each

Resend for: - New projects in the React ecosystem - Teams that want fast developer iteration - Anyone using React Email or wanting to - Mid-volume work (millions per month)

SendGrid for: - Larger enterprises with broad email needs (transactional + marketing) - High-volume operations (tens of millions per month) - Teams that need deep analytics or advanced automation

Postmark for: - Critical transactional work where deliverability is paramount - Magic links and password resets where every email matters - Smaller teams that want a focused, reliable product

What I default to

For new projects: Resend. The developer experience wins. React Email is genuinely transformative for templated transactional emails.

For projects where every email matters (auth, payment receipts): Postmark for transactional, Resend for everything else.

For enterprise migrations: keep SendGrid if it's already working. The switching cost rarely justifies the savings.

What surprised me about each

Resend: their batch sending API is much better than I expected. For mass-personalized sends (say, monthly customer reports), Resend handles it cleanly.

SendGrid: their UI is dated but the underlying infrastructure is rock-solid. Don't judge by the dashboard.

Postmark: their support is excellent. Real engineers, fast responses, willingness to help debug specific deliverability issues.

The deliverability question

For high-stakes emails (account verification, password resets) deliverability is the entire product. The best API in the world doesn't matter if the email lands in spam.

All three providers do well on deliverability for clean senders. Postmark has a slight edge for the highest-stakes transactional work. SendGrid is reliable at scale. Resend is competitive but younger — track record is shorter.

For most projects, all three are fine on deliverability. For projects where one missed email is catastrophic, lean toward Postmark.

The pricing math

At 100k emails/month: - Resend: ~$20/month - SendGrid: ~$30-50/month depending on features - Postmark: ~$10/month

At 1M emails/month: - Resend: ~$200/month - SendGrid: ~$90-150/month - Postmark: ~$100/month

Postmark is cheapest at most volumes. SendGrid gets competitive at very high volumes. Resend is mid-range.

What I'd tell someone starting

Default to Resend for new projects. The DX advantage is real and pays back over the project's life.

Default to Postmark if deliverability is your #1 concern.

Default to SendGrid only if you're already on it or have specific enterprise needs.

All three are good products. The choice is about fit, not about which is "best" in the abstract.