Article
Which email API is cheapest for a small product?
By Brightiny9Published
From 10,000 emails a month up, Amazon SES is the cheapest we could price; free plans cover less. Prices checked 2026-11-01 on vendor pages.
Of the vendors we could price, Amazon SES is the cheapest from 10,000 emails a month up: $0.16 per 1,000 emails, checked 2026-11-01. Below that, the free plans at Resend and Mailgun cost $0. Resend costs roughly 2 to 12 times more than SES; paid plans at Mailgun and Postmark start at $15.
| Emails per month | Amazon SES | Resend | Mailgun | Postmark | Priced on |
|---|---|---|---|---|---|
| 1,000 | $0.16 | $0 (free plan) | $0 (free plan) | $15 | 2026-11-01 |
| 10,000 | $1.60 | $20 | $15 | $15 | 2026-11-01 |
| 20,000 | $3.20 | $20 | up to $33 | up to $29.50 | 2026-11-01 |
| 50,000 | $8.00 | $20 | $35 | up to $66 | 2026-11-01 |
| 60,000 (spike month) | $9.60 | $29 | up to $48 | up to $78 | 2026-11-01 |
| 100,000 | $16.00 | $35 | $90 | up to $126 | 2026-11-01 |
| 500,000 | $80.00 | $350 | up to $530 | up to $606 | 2026-11-01 |
| 1,000,000 | $160.00 | $650 | up to $1,080 | up to $1,206 | 2026-11-01 |
Prices are list prices before tax. Sources: Amazon SES pricing, Resend pricing, Mailgun pricing, Postmark pricing, all checked 2026-11-01. "Up to" means our upper bound: a plan's base price plus its list overage rate for every email above the included volume (Mailgun words its rates as "from"). Both Mailgun and Postmark also show a volume selector for larger tiers. In a browser on 2026-11-01 Postmark's selector listed 10,000, 50,000, 125,000, 300,000, 700,000 and 1,500,000 emails; the prices behind it do not appear in the page text, and we did not read them, so real tier prices may be lower. SendGrid is covered below because its page shows only starting prices.
How we priced each workload
We picked seven monthly volumes plus one spike month, then took the cheapest way to send that many emails from the prices we could read. The rule for each cell, using prices checked 2026-11-01:
- Amazon SES: volume ÷ 1,000 × $0.16, the Essentials rate for the first 10 million emails. SES also lists monthly plans, Pro at $105 and Enterprise at $500, which we did not use (checked 2026-11-01).
- Resend: the plan that includes the volume (Free $0, Pro $20 for 50,000, Pro $35 for 100,000, Scale $350 for 500,000, Scale $650 for 1,000,000). The 10,000 row needs Pro because the free plan stops at 3,000. The spike month uses Pro $20 plus 10,000 extra emails at $0.90 per 1,000 (checked 2026-11-01).
- Mailgun: the cheaper of the plan that fits, or a smaller plan plus overage. Basic is $15 for 10,000 with $1.80 per extra 1,000. Foundation is $35 for 50,000 with $1.30. Scale is $90 for 100,000 with $1.10. The 500,000 and 1,000,000 cells are Scale plus list overage (checked 2026-11-01).
- Postmark: each paid plan includes 10,000 emails: Basic $15 with $1.80 per extra 1,000, Pro $16.50 with $1.30, Platform $18 with $1.20. We took the cheapest of the three. Example: 20,000 emails on Pro cost $16.50 + 10 × $1.30 = $29.50. At 1,000 emails the free plan holds only 100 a month, so the cell shows the $15 Basic plan (checked 2026-11-01).
The dev.to post of 2026-10-07 asked the same question and also found SES cheapest. We used its idea, not its numbers. Every price comes from the vendor pages; the sums are ours.
How much cheaper is SES, really?
Divide each provider's bill by the SES bill, from the table above (our calculation, prices of 2026-11-01). The Mailgun figures at 500,000 and above are upper bounds.
| Emails per month | Resend ÷ SES | Mailgun ÷ SES |
|---|---|---|
| 10,000 | 12.5 | 9.4 |
| 20,000 | 6.3 | up to 10.3 |
| 50,000 | 2.5 | 4.4 |
| 100,000 | 2.2 | 5.6 |
| 500,000 | 4.4 | up to 6.6 |
| 1,000,000 | 4.1 | up to 6.8 |
The gap to Resend is smallest at 100,000 emails, where Resend's $35 plan costs $0.35 per 1,000 sent. Resend's Scale plans cost more per 1,000: $0.80 at 200,000 emails and $0.70 at 500,000 (checked 2026-11-01, Resend pricing).
In dollars, compared with Resend, SES saves $19 a month at 100,000 emails, or $228 a year. At 500,000 it saves $270 a month, or $3,240 a year. Compared with Mailgun at 100,000 emails, SES saves $74 a month (our calculation, prices of 2026-11-01). Our view: against Resend, below about 100,000 emails a month the saving is small, so pick on convenience. At 500,000 and up, it is large enough to weigh against your own setup time. We did not measure that time.
Where each plan changes shape
Mailgun's Basic plan with overage beats its Foundation plan only up to a point. Basic costs $15 + $1.80 per extra 1,000 emails over 10,000. Foundation costs $35. They cross at 21,100 emails (15 + 1.8 × 11.1 = 35). Foundation with overage meets Scale at 92,300 emails (35 + 1.3 × 42.3 = 90). Prices checked 2026-11-01 on the Mailgun pricing page. Above those points, upgrading beats paying overage.
A launch month shows why plan choice matters. Take a 20,000-email product that sends 60,000 in one month. On Mailgun Basic that is $15 + 50 × $1.80 = $105. On Foundation it is $35 + 10 × $1.30 = $48. On SES it is $9.60. On Resend Pro it is $29. The same volume costs $105 or $48 depending on which Mailgun plan you were on when the spike hit (prices checked 2026-11-01).
What a dedicated IP costs at 100,000 emails
A dedicated IP gives you your own sending reputation. At 100,000 emails a month it costs this much:
- Amazon SES, standard dedicated IP: $16 for the emails plus $24.95 a month per IP, so $40.95 (our sum, Amazon SES pricing, checked 2026-11-01). The page describes this option as manual management of warm-up and pools.
- Mailgun Scale: $90, with one dedicated IP included (Mailgun pricing, checked 2026-11-01).
- Resend Scale: $90 plus a $30 monthly add-on, so $120. Resend says dedicated IPs need more than 3,000 emails a day (Resend pricing, checked 2026-11-01).
- Postmark: from $50 a month per IP, and only for senders at 300,000 emails a month or more, on Pro or higher, so not available at 100,000 (Postmark pricing, checked 2026-11-01).
- SES also sells managed dedicated IPs at $15 a month per account plus per-email fees. We did not total these, because we could not tell how the fees stack on the base rate (checked 2026-11-01).
Does the free plan cover a side project?
Resend's free plan allows 3,000 emails a month, but also "100 emails a day" (Resend quotas doc, checked 2026-11-01). A product that sends 1,000 emails a month can still be blocked on a day with 500 sign-up emails. Mailgun's free plan has the same 100-a-day shape (Mailgun pricing, checked 2026-11-01). Resend also counts every To, CC and BCC recipient as one email, so one message to three people uses three.
Does Amazon SES have a free tier?
Only as credit for new AWS accounts. The page says new customers get up to $200 in credits. It ties a free plan to 6 months after account creation and says credits must be used within 12 months (Amazon SES pricing, checked 2026-11-01). We found no monthly free allowance on the page. SES also lists an "à la carte" rate of $0.10 per 1,000 emails, 37.5% below the $0.16 Essentials rate we used. We used the higher rate and did not check what à la carte leaves out.
Does SendGrid still have a free plan?
Not on its pricing page. Its free trial lasts 60 days and allows 100 emails a day. After that come Essentials from $19.95 a month and Pro from $89.95 a month with one dedicated IP (Twilio SendGrid pricing, checked 2026-11-01). The page lists volume tiers from under 3,000 up to 5,000,000 or more emails, but no price for each tier in text. That is why SendGrid has no column in our table.
Choose Amazon SES if
- You send 10,000 or more emails a month and want the lowest bill.
- You can build the pieces around it yourself. The dev.to post of 2026-10-07 lists webhooks and logs as hidden costs of SES.
- You already run on AWS.
Choose Resend if
- You want a working integration fast and a flat monthly price.
- You send under 100,000 emails a month and the gap to SES is under $20 (prices of 2026-11-01).
Choose Mailgun if
- You want a dedicated IP at around 100,000 emails and one included in the plan. Mailgun Scale does that at $90; SES is cheaper at $40.95 but you manage warm-up and pools yourself (prices of 2026-11-01).
Choose Postmark if
- You send well under 10,000 emails a month and want a 45-day default message history, which you can extend up to 365 days on Pro (Postmark pricing, checked 2026-11-01).
What we did not check
- The prices behind Postmark's and Mailgun's volume selectors.
- SendGrid prices per volume tier.
- Delivery rates, support and setup time. This article compares price only.
- SES sandbox limits, bounce and complaint handling, and each vendor's rules on cold email.
- SES data transfer fees, which the dev.to post mentions and we did not check.
- Taxes, currency conversion and enterprise discounts.
Related reading
- The stack-cost article prices a whole solo-founder stack from list prices, checked 2026-10-16.
- The customer-count article turns monthly prices into paying-customer counts, checked 2026-11-01.
How we researched this
We read the vendor pricing pages on 2026-11-01 and calculated every cell ourselves from the formulas above. We did not test these products hands-on. Prices change; re-check the linked pages before you buy. This article has no ads or affiliate links.
Changelog
- 2026-11-02: First published. All prices were read on 2026-11-01 and the table was not changed after that.