SendGrid alternatives: transactional email APIs
Updated Nov 9, 2026. Listed A to Z, not ranked. Prices change often: confirm with each provider.
SendGrid is a long-running email API. If you are comparing options for transactional or product email, these are the alternatives with published pricing, plus email tools built for AI agents from our directory, A to Z.
SendGrid’s own pricing page did not show readable plan prices when we checked, so it is not in the table; see sendgrid.com for current plans. Head-to-heads: Mailgun vs Postmark, Postmark vs Resend.
Published email API pricing (for reference)
| Provider | Published pricing | Notes |
|---|---|---|
| Mailgun | Free 100/day; Basic $15/mo (10k); Foundation $35 (50k) / $75 (100k); Scale from $90 (100k) | Overage from $1.80 down to $0.40 per 1,000 |
| Postmark | Free 100/mo; Basic $15, Pro $16.50, Platform $18 for 10,000 emails | Overage $1.80 / $1.30 / $1.20 per 1,000 |
| Resend | Free 3,000/mo; Pro $20 (50k); Scale $90 (100k) | Overage $0.90 per 1,000 |
Quoted from each provider’s official pricing page on Nov 9, 2026.
Email tools for AI agents in our directory (2)
| Tool | What it does | How you pay | Published price | Links |
|---|---|---|---|---|
| AgentMail | Email inbox API for AI agents: create inboxes, then send, receive and search messages over REST. An x402 gateway lets agents pay per request with no account. | USDC per call (x402) | $0 per call (listing) (checked 2026-10-22) | Listing · Pricing |
| ai-mail.sh | Receive-only email addresses for AI agents, bought over x402: a day or a month per address. Reading is free, and codes and verification links are extracted for you. | USDC per call (x402) | $0.05–$1 per call (listing) (checked 2026-10-26) | Listing |
Choosing an alternative
- Volume sending: Mailgun’s Scale tiers go to 2.5M emails a month.
- Transactional focus: Postmark separates plans by retention and overage.
- Developer API: Resend has one overage rate on paid plans.
- Inboxes for agents: AgentMail and ai-mail.sh give AI agents their own addresses to send or receive mail.
FAQ
- What is a good SendGrid alternative?
- Mailgun, Postmark and Resend are common choices for transactional email; AgentMail and ai-mail.sh focus on inboxes for AI agents. We list them A to Z, not ranked.
- How much does Resend cost compared with Postmark?
- On Nov 9, 2026 Resend Pro was $20 a month for 50,000 emails; Postmark Basic was $15 a month for 10,000.
Sources (read Nov 9, 2026): www.mailgun.com/pricing/ · postmarkapp.com/pricing · resend.com/pricing
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