Your first 10k emails: what transactional email really costs at launch

Launch-stage email is a solved problem that everyone solves badly, because the pricing pages make comparison nearly impossible: one vendor counts recipients, another counts messages, a third bundles marketing sends with transactional ones, and the fourth quotes "from $0" in type large enough to need its own viewport. We built an email API comparison tool on top of a captured catalog of eleven vendors (verifiedAt 2026-08-22 from official pricing sheets — Mailchimp/Mailersend/SMTP2GO re-captured that week from mailchimp.com/pricing, mailersend.com/pricing, smtp2go.com/pricing), and pointed its standard startup scenario at them: 10,000 emails per month, 95% transactional — auth mails, password resets, receipts, notification streams — priced through the same pure compute engine the live tool uses, so the article and the app cannot drift apart.

The result: at launch volume, email should be free

The ranking is no longer about who advertises free. After the 2026-08-22 gating fix, no vendor quotes $0 at 10k under default conditions: Brevo's 300/day and SMTP2GO's 200/day both block when you average 328/day, and SES's 62k EC2-only allowance is explicitly not applied to default app-infra senders. The cheapest honest bill is therefore SES at $1.00 — pure pay-per-thousand at $0.10/1k, no base, no cap. Next is Scaleway at ≈$2.49 (€2.30 at 1.08), then Brevo at ≈$4.89 once the daily cap removes its headline. The most expensive position — Mailgun's $35.17 Foundation for 50k — costs 35× more than SES for the identical 10k job, and the spread between cheapest and median (MailerSend $13.04) still funds a month of VPS on Hetzner. That is why our live ranking sorts on the computed totalCost (normalized once via fx.ts at 1.08, FX_AS_OF 2026-08-20) rather than on the marketing headline, and why the table above carries the engine's notes verbatim.

Read the shape, not just the number

The zero-dollar rows are not all the same deal, because free tiers carry two kinds of asterisks that our calculator now checks explicitly (a correction we shipped in August 2026). First, daily caps: Brevo's 9,000/month headline is actually 300/day — 300 × 30.44 = 9,132/month is what a perfectly spread month can absorb, so a workload that averages 328/day (10,000 ÷ 30.44 ≈ 328) exceeds it and gets zero free allowance in our default quote. SMTP2GO's 1,000/month is similarly capped at 200/day (200 × 30.44 = 6,088/month) — daily volume above that, even if monthly volume looks inside the allowance, loses the free tier and falls to the Starter $15/mo for 10k included. That 30.44-day divisor (365 ÷ 12, the honest mean month) is how our calculator gates free allowances: it compares your average daily volume against each provider's daily cap, and when a workload would exceed the cap the allowance is skipped — with a visible note saying why. Second, conditional allowances: AWS SES's 62,000-message monthly free allowance is the largest in the market by an order of magnitude — $0.10 per 1,000 beyond ($1.00 for 10k) is itself the price floor — but it applies only to email sent from EC2 — flagged as EC2-only in our dataset. The default visitor sends from their own app infra, not EC2, so our ranking quotes SES at $1.00 (10k × $0.10/1k) and discloses that EC2 senders' real price is lower in the notes. Scaleway TEM is cleaner: its Essential pay-as-you-go now includes only 300 emails, then €0.25 per 1k — at 10k that is (9,700 ÷ 1,000 × €0.25) = €2.425 ≈ $2.62 at 1.08 — no daily cap, no condition, but no generous free tier either.

Methodology: from catalog to $/month without guessing

Every price in this piece was captured by hand from the vendor's own pricing page on 2026-08-22 — eleven vendors made the cut, each with its per-thousand rates, plan fees, included monthly volumes, free-tier limits (including daily caps like Brevo's 300/day), fine print (SES's free tier only applies from EC2), and feature set (webhooks, SMTP relay, inbound routing, React SDKs, sub-accounts) recorded with a source link. Vendors whose self-serve pricing can't be fully captured stay out entirely rather than getting estimated numbers — vendors without capturable self-serve rates (SparkPost, Bird, Elastic Email) stay out per the documented inclusion criterion (market-leading + fully capturable + affiliate-prioritized). Our calculator then turns those captures into the ranking you see: the free allowance is gated on daily caps and fine print; the billable volume is split by how much of your sending is transactional versus marketing (95% here); each stream is priced from the plan or rate band that covers it, including overages past what the plan includes; and base plan fees are never double-counted on top of a tier that already charges one. Euro prices convert once at our recorded rate ($1.08 per euro, as of 2026-08-20) so vendors are compared honestly on total cost while displayed in their native currency, so Brevo's €19/mo Starter and Mailjet's €15/mo Essential are compared honestly on totalCost (converted) while displayed natively. The table above is therefore not a hand-typed illustration — it is the live ranking for the 10k/95% input you see on the email tool.

When does the free ride end?

• Volume cliff: every free tier ends at a hard number and then you jump to the first paid plan — there is no smooth metering between "free" and "entry plan" on most vendors. Brevo's jump is 300/day; SMTP2GO's is 200/day — your burst day, not your month, decides.
• Daily vs monthly: at 10k/month you average 328/day — already above Brevo's 300/day even inside the 9,000 headline, so the honest month-one cost for a spiky launch can be paid despite the headline. Model bursts, not just means.
• Feature gates matter earlier than volume: dedicated sending IPs ($29 Brevo, $50 Postmark, bundled free on Scaleway Scale €80/mo with 100k + SLA), sub-accounts, and advanced webhooks are typically paid-plan features regardless of how few emails you send.
• Growth math: at 75k/month (our Growth App scenario) the board reshuffles completely — the vendors that were free at 10k are now mid-priced and the flat-rate entrants look different. At 250k and 2.5M the cheapest paid vendor changes again; check the growth presets before you lock in an SDK.
• EU residency requirements can disqualify otherwise-cheap options instantly; filter before comparing, not after — Scaleway (EU-sovereign, GDPR residency in Europe) and Brevo (EU-sovereign) stay eligible when US-only vendors don't.

Who should pick what

If you are pre-product-market-fit and sending <10k onboarding + transactional mails with occasional bursts, Brevo's 300/day can cover you if you smooth sends, but don't architect around a cap that punishes your launch week — SES at $1.00 with no daily cap is the cheapest caveat-free bill if you accept its setup ceremony (sandbox approval, DNS verification, managing your own reputation). If you are EU-resident and want sovereignty from day one, Scaleway's €2.43 net (~$2.62 normalized) plus the same tool's VPS and domain EUR honesty gives you one FX story across the stack; at 75k, Scaleway's Scale €80 bundle with its managed IP overtakes Brevo on predictable cost. If you value deliverability polish from day one — template builder, 45-day analytics, sub-accounts, inbound routing — Postmark's $15 for 10k included is not a premium brand tax but a bundle of those captured features (score 7/7 on our count) with a reputation for speed and support; whether it is worth $180/year on a 10k-month workload is a question only your open-rate data and your need for object storage CDN coupling can answer. In every case, choose your free tier by where you expect to be in six months, because that's when these prices start to diverge sharply — not by what is free today.

The honest summary for founders: at launch volume, do not pay for transactional email — but choose your free tier by its daily cap and its caveat, not its monthly headline, because that's when the bill arrives. The full interactive picture, including 250k and 2.5M-volume scenarios, per-vendor feature matrices, the 30.44-day gating note, and the EC2-caveat disclosure, lives in the comparison tool. All prices captured 2026-08-22 from vendor pricing pages; where a vendor publishes no figure, our catalog records the absence rather than guessing — the same honest-null discipline we apply on VPS SLAs and domain ICANN flags.