At a million emails a month, the per-email rate stops being a rounding error and starts being a real line item. Here is what each provider costs at that scale, and when paying more is still the smart move. Figures are a June 2026 snapshot.
Estimate — verify with each vendor. Volume pricing, overage and add-ons (dedicated IPs) vary; confirm on the vendor’s page.
The answer first
| Provider | Cost per 1,000 | ~Cost for 1,000,000/month |
|---|---|---|
| Amazon SES | $0.10 | ~$100 |
| Resend | ~$0.40 | ~$400 |
| SendGrid | ~$0.40 | ~$400 |
| Mailgun | ~$0.70 | ~$700 |
| Postmark | $1.50 | ~$1,500 |
Amazon SES wins by a wide margin. Confirm at your exact volume with the email cost calculator, and see the full email API comparison.
Why SES dominates at scale
SES is pure pay-as-you-go infrastructure — there is no product markup, no monthly platform fee, just $0.10 per 1,000 emails plus a small attachment-bandwidth charge. The managed providers bundle dashboards, templating, analytics and deliverability into a higher per-email price, which barely matters at 5,000 emails but compounds into thousands of dollars at a million.
What you trade away
The reason not everyone uses SES at scale: it is infrastructure, not a product. You build your own:
- Templating and personalization
- Analytics and engagement tracking
- Bounce/complaint suppression handling
- Sending-reputation warm-up and deliverability monitoring
For a small team, the time cost of building all that can exceed the price gap — which is exactly why SendGrid, Resend and Postmark exist. Weigh it in the SendGrid vs SES matchup.
The practical recommendation
- High volume, engineering capacity: Amazon SES — save ~$300–$1,400/month at a million emails.
- High volume, small team: SendGrid or Resend at ~$400 buys you a managed product.
- Deliverability is mission-critical: Postmark — you pay for speed and reputation.
For lower volumes, see the cheapest transactional email API in 2026.
Sources and accuracy
Per-1,000 rates are snapshots of each vendor’s public pricing page captured in June 2026; the million-email figures are simple extrapolations and ignore volume discounts and add-ons. Estimates only — verify before relying on them. See our methodology.