Every email API prices differently. Some sell monthly tiers, some bill per email, and some charge for newsletters separately. So I priced the same seven workloads on Amazon SES, Mailgun, Postmark, Resend, SendGrid and SMTPfast.
Prices come from the official pricing pages on October 6, 2026, in USD. Sources are at the bottom.
TL;DR
Monthly cost, cheapest first.
- Side project (1,000 emails): Mailgun $0 · Resend $0 · SMTPfast $0 · SES ~$0.11 · Postmark $15 · SendGrid $19.95
- Early SaaS (20,000 emails): SES ~$2 · SMTPfast $19 · SendGrid $19.95 · Resend $20 · Postmark $29.50 · Mailgun $33
- Growing SaaS (100,000 emails): SES ~$11 · SendGrid $34.95 · Resend $35 · SMTPfast $49 · Mailgun $75 · Postmark $115
- High volume (500,000 emails): SES ~$53 · SMTPfast $349 · Resend $350 · SendGrid ~$387 · Mailgun $400 · Postmark $455
- 1M emails: SES ~$106 · Resend $650 · Mailgun $700 · SendGrid $733 · Postmark $775 · SMTPfast $849
- Newsletter (5,000 contacts, 4 sends): SES ~$2* · SMTPfast $19 · SendGrid $25 · Postmark $29.50* · Mailgun $33* · Resend $40
- Launch spike (20k plan, 60k month): SES ~$6 · Resend $29 · SMTPfast $29 · SendGrid ~$33 · Postmark ~$82 · Mailgun $105
*Sending only, with no contact lists or broadcast tools included.
Once you're past the free tiers, Amazon SES is the cheapest at every volume, by 3–10×. But it's raw infrastructure. Webhooks, logs and templates are yours to build. Among full email APIs, the cheapest option changes with volume: SMTPfast at 20k and 500k, SendGrid and Resend at 100k, and Resend at 1M.
How each one charges
- Amazon SES: $0.10 per 1,000 emails plus $0.12/GB of data. Since July 2026, new accounts default to a $0.16 plan, and you can switch back to $0.10 at any time.
- Mailgun: monthly tiers from $15 (10k emails). Extra emails cost $0.40–$1.80 per 1,000 depending on the tier.
- Postmark: monthly tiers from $15 (10k emails). Extra emails cost $1.15–$1.80 per 1,000.
- Resend: $20 (50k) or $35 (100k), then Scale from $90. Extra emails cost $0.46–$0.90 per 1,000 once you turn overage on. Newsletters are billed separately, per contact.
- SendGrid: Essentials from $19.95 (50k), Pro from $89.95 (100k, with a dedicated IP). Extra emails cost $0.47–$1.33 per 1,000. Newsletters are a separate product.
- SMTPfast: $9 (10k), $19 (50k) or $49 (200k), with newsletters included. Extra emails come from prepaid credits at $1 per 1,000. It runs on Amazon SES.
Free tiers
- Amazon SES: no free tier for new accounts since July 2026, only AWS credits ($100–200). New accounts start in a sandbox that sends 200 emails a day to verified addresses until AWS approves you.
- Mailgun: 100 emails a day, 1 domain, 1 day of logs. No card, but without one you can only send to 5 verified addresses.
- Postmark: 100 emails a month, forever. No card. Postmark approves your account manually before you can email other domains.
- Resend: 3,000 emails a month (100 a day), 3 domains, 30-day logs, inbound included. No card.
- SendGrid: no free plan since 2025, only a 60-day trial at 100 emails a day.
- SMTPfast: 3,000 emails a month, 1 domain, 1,000 contacts, 2 broadcasts. No card. Sending access is reviewed before you can send.
The scenarios
SES numbers assume about 50 KB per email and the $0.10 rate. Open "Show the math" under each one for the full calculation.
1. Side project
1,000 emails a month: magic links, password resets and receipts.
Free tiers decide this one. Mailgun, Resend and SMTPfast cover it for $0. Postmark's free 100 a month doesn't, and SendGrid's trial ends after 60 days.
Show the math
2. Early SaaS
20,000 transactional emails a month.
SMTPfast, SendGrid and Resend all land around $20 with room to grow to 50k. Plans that start at 10k pay overage for the second 10k.
Show the math
3. Growing SaaS
100,000 emails a month.
SendGrid and Resend both have a 100k tier around $35. SMTPfast's next tier jumps to 200k for $49.
Show the math
4. High volume
500,000 and 1M emails a month.
At 500k, SMTPfast and Resend tie at about $350. At 1M, SMTPfast becomes the most expensive here, because every email past 200k costs $1 per 1,000 in credits.
1,000,000 emails:Show the math
500,000 emails:
5. Newsletter
5,000 contacts, 4 sends a month (20,000 emails).
Only SMTPfast, SendGrid and Resend include contact lists and broadcasts. SMTPfast is the cheapest of the three because it doesn't bill newsletters as a separate product.
Show the math
6. Launch spike
You're on the plan from scenario 2, and a launch month sends 60,000 emails.
Plans that include 50k absorb most of the spike. Plans that start at 10k pay $1.30–$1.80 for every extra 1,000.
Show the math
Hidden costs
- Amazon SES: webhooks need SNS or EventBridge, per-message logs need the paid deliverability dashboard, and a dedicated IP is $24.95/month.
- Mailgun: overage can't be turned off. The $15 plan has 1 domain and 1 day of logs; 30-day logs need Scale ($90+).
- Postmark: overage can't be capped. The Basic plan has no inbound email, and DMARC monitoring is $14 per domain per month.
- Resend: every To, CC and BCC address counts as an email. Newsletters are billed per contact on top of transactional.
- SendGrid: Essentials has no dedicated IP option and only 3 days of activity history.
- SMTPfast: no dedicated IPs on any plan. Extra emails cost $1 per 1,000, about 4× its effective Scale rate, and sends are rejected once the allowance and credits run out.
Which one should you pick?
For most startups: SMTPfast
- $0 to start: 3,000 emails a month, no credit card.
- $19 covers a lot: 50k emails, unlimited domains and open/click tracking (scenario 2).
- Newsletters included: contacts, segments and broadcasts in the same plan (scenario 5).
- No surprise bills: extra emails come from prepaid credits, so you never get an overage invoice.
- Easy to switch: the API is Resend-compatible, so moving is a base-URL and API-key change.
Revisit the choice past about 300k emails a month or when you need a dedicated IP. At 1M, Resend or SES directly costs less.
Everything else
- Amazon SES: the lowest price at any volume, if you're happy to build webhooks, logs and templates yourself.
- Mailgun: many domains, inbound routing, and a dedicated IP from $75/month.
- Postmark: 45-day logs and the same support on every plan.
- Resend: the cheapest full API at 1M emails, and the 100k tier at $35.
- SendGrid: 100k for $34.95, plus a marketing suite with automation on its Advanced plans.
Sources
Prices checked October 6, 2026.
- Amazon SES: pricing, pricing plans, sandbox
- Mailgun: pricing
- Postmark: pricing, billing FAQ
- Resend: pricing, quotas and limits
- SendGrid: Email API pricing, Marketing Campaigns pricing, free plan change
- SMTPfast: pricing, prepaid credits
Top comments (4)
Putting the same seven workloads next to each other is the useful part — most of these pages are impossible to compare otherwise. At early SaaS volume SES is basically free, but did deliverability or support ever push you off it toward something like Postmark?
Your cost breakdown is the honest version — SES wins on price at every volume, then hands you the webhooks, logs and templates to build yourself. That build-it-yourself layer is what I'm working on with rootmail: per-message delivery state on top of SES instead of raw events. Invite-only beta right now — happy to open a seat if you want to see how the numbers change when the plumbing's already there.
denis, this is an incredibly valuable breakdown. saving devs hours of pricing-page math is a huge service to the community.
i just set up the email pipeline for my newsletter (off radar) and was evaluating these exact options. your point about the "hidden costs" of amazon ses is spot on. the $0.10/1k looks great on paper until you factor in the engineering hours required to build your own webhook logging, bounce handling, and templating. for a solo builder, paying $19–35 for a managed api is almost always the cheaper choice when you value your own time.
one honorable mention for the "side project / early saas" tier is brevo (formerly sendinblue). their free tier gives 300 emails/day (9,000/month) with contact management and basic automations included, which is a massive win for solo devs before hitting the 50k mark where resend and smtpfast really shine.
thanks for the rigorous research and for keeping this updated for 2026! 🐯
Bài viết rất hữu ích để có cái nhìn tổng quan, nhưng thực tế triển khai thường gặp thêm vài "chi phí ẩn" không hề nhỏ:
Warm-up & reputation — Các provider thường không tính tiền giai đoạn này, nhưng team phải dành 2-4 tuần (hoặc hơn) để build reputation trước khi scale. Với workloadTransactional volume cao, việc này trực tiếp ảnh hưởng time-to-revenue.
Deliverability monitoring — Giá base không bao gồm tooling theo dõi inbox placement, spam trap hits, blocklist alerts. Nếu tự build stack này (webhook parsing, seed list testing, feedback loop processing) thì effort engineering không hề nhỏ.
Dedicated IP vs shared pool — Nhiều provider ép buộc mua dedicated IP khi vượt threshold nhất định (thường 100k-500k/tháng). Chi phí IP + quản trị reputation tách biệt hoàn toàn so với pricing table công khai.
Regional compliance — GDPR, CAN-SPAM, CASL, LGPD (site: labagent .tech)