The cheapest way to send transactional email in 2026

Every application sends two very different kinds of email, and they are billed on completely different meters. The newsletter is marketing email: it goes to a stored list, and providers charge you by how many contacts you keep. The password reset, the receipt, the verification code and the shipping notification are transactional email: they go to one person, once, triggered by something that person just did, and providers charge you by how many you send. Confusing the two is how people end up either overpaying or getting a surprise bill, because a price that looks fine for one model can be wrong for the other.

Why transactional pricing looks so different

On the marketing side, the cost driver is list size. Mailchimp, Klaviyo and Brevo's marketing plans bill by how many contacts you store, whether or not you email them, which is the whole subject of our piece on why your Klaviyo bill is mostly contacts you never email. Transactional email has no stored audience to charge for: there is no list, just a stream of one-off messages. So the meter is volume sent. That single difference is why the numbers below range from about a dollar to nearly two hundred for the same 100,000 emails: the providers are not selling the same thing at different prices, they are making different bets about how much tooling to wrap around the send.

The two pricing models

Underneath the six providers there are really two models. The first is pure pay-as-you-go metered sending, which in practice means Amazon SES: no monthly base fee, you pay per email and nothing else, and you get a bare API. The second is a flat monthly plan with an included volume and an overage rate, which is how Postmark, Resend, SendGrid, Mailgun and Brevo all work: you pay a base fee that bundles templates, a dashboard, analytics, bounce and complaint handling and support, and you pay overage once you exceed the tier. The metered model is cheapest per email and most work to run; the flat model costs more per email and hands you the tooling. Everything else is a variation on that trade.

Amazon SES: cheapest to send, most to build

SES is the price floor. It charges 0.10 dollar per 1,000 emails sent, plus 0.12 dollar per GB of attachments, with no monthly fee. At 10,000 emails a month that is about a dollar; at 100,000 it is about 10 dollars. Nothing else on this page comes close on raw price. What you get for that is exactly an API that sends mail: there is no template editor, no analytics dashboard worth the name, and the deliverability tooling, warm-up, bounce and complaint handling and monitoring are yours to build or bolt on. There is also no permanent free tier any more, only 3,000 message charges a month for the first 12 months on a new account. SES is the right answer when you have engineers, real volume and a reason to care about the bill, and the wrong answer when you wanted email to be a solved problem out of the box.

Postmark: you pay for the receipt arriving

Postmark sits at the premium end and does it deliberately. Its Basic plan is 15 dollars a month for 10,000 emails, with overage at 1.80 dollar per 1,000; the Pro and Platform tiers keep the same 10,000 included and drop the overage to 1.30 and 1.20 dollar. At low volume that is competitive, but the overage is steep, so 100,000 emails a month works out to about 177 dollars (15 dollars plus 90,000 at 1.80 dollar per 1,000). The reason to pay it is that Postmark is built around transactional deliverability: fast delivery, transactional and broadcast streams kept separate so a marketing send cannot hurt your receipt reputation, and detailed delivery data. When the email that must not fail is the password reset or the payment receipt, Postmark's pitch is that the premium buys you the confidence it arrives.

Resend: the modern developer experience

Resend is the provider newer projects tend to reach for, because it puts a clean API and dashboard first. The free tier is 3,000 emails a month, capped at 100 a day; the Pro plan is 20 dollars a month for 50,000 emails or 35 dollars for 100,000, with overage at 0.90 dollar per 1,000, and Scale tiers run from 90 dollars upward for higher volume. It ships React Email so you build templates in code rather than a drag-and-drop editor, which suits teams that want their email in the same repository as their app. It is more expensive per email than SES and much less setup, and at 100,000 sends its 35 dollars undercuts Postmark's 177 by a wide margin. For most teams that want a good API without owning the tooling, Resend is the balance point.

SendGrid: the free tier that went away

SendGrid, now part of Twilio, was the default for years, largely on the strength of a permanent free plan. That plan ended in 2025, replaced by a 60-day trial capped at 100 emails a day, and that change is the single biggest reason projects went shopping in 2025 and 2026. Paid, Essentials starts at 19.95 dollar a month for 50,000 emails and Pro at 89.95 dollar a month scaling toward 2.5 million. It remains a capable, mature platform, but two things are worth knowing: there is no longer a free on-ramp, and marketing and transactional email share the same monthly volume cap, so if you run both through SendGrid they spend from one number. It is still a reasonable choice, just no longer the obvious free default it used to be.

Mailgun and Brevo: the middle

Two more fill out the middle. Mailgun is a developer-focused sender priced in clean tiers: Basic is 15 dollars for 10,000 emails, Foundation 35 dollars for 50,000, and Scale 90 dollars for 100,000, with overage on the lower tiers around 1.80 dollar per 1,000. It is a straightforward metered-plus-plan option that sits between SES on price and Postmark on polish. Brevo is the other kind of middle: it is the only provider here that runs transactional and marketing email from one account, so a small business can send its receipts and its newsletter without two separate vendors. Its free tier sends 300 transactional emails a day, about 9,000 a month, with unlimited stored contacts, and the Starter plan from 9 dollars a month removes the daily cap. Neither wins on pure price, but both are sensible when the pure-metered SES route is more than you want to run.

The same volume, six very different bills

Line them up at two scales and the models separate. At 10,000 emails a month you are looking at roughly a dollar on SES, 15 dollars on Postmark Basic or Mailgun Basic, 20 dollars on Resend Pro, 19.95 dollars on SendGrid Essentials, and free-to-9-dollars on Brevo, so the flat plans cluster and SES is the outlier on price. At 100,000 a month the gap widens hard: about 10 dollars on SES, 35 dollars on Resend, 90 dollars on Mailgun Scale, 89.95 on SendGrid Pro, and about 177 dollars on Postmark once the overage stacks up. Same 100,000 messages, and the bill ranges from 10 to 177 dollars depending only on how much tooling and deliverability assurance you are buying alongside the send. That spread, not any single sticker, is the thing to understand before you pick.

The line the per-send price skips: a dedicated IP

Every bill above is the shared-pool price, where your mail leaves from IP addresses the provider also lends to other senders. Past a certain volume the deliverability advice flips to a dedicated IP, an address only you send from, and that is a separate monthly line the per-send comparison hides. Amazon SES charges 24.95 dollar a month for a standard dedicated IP, or 15 dollar a month plus 0.08 dollar per 1,000 emails for its managed version that warms the IP up for you automatically. Postmark's dedicated IP is 50 dollar a month and gated to its Pro tier at 300,000 emails a month or more. SendGrid's Pro plan includes one dedicated IP, and extra ones run from about 30 dollar a month. Mailgun includes one on its 100,000-email Foundation, Growth and Scale plans and charges about 59 dollar a month for more. Resend offers dedicated IPs only on its Scale tier and above and does not publish the price. So the moment you decide you need one, the cheapest-sticker ranking can reshuffle.

The trap is buying one too early. A dedicated IP has no sending reputation on day one, so it has to be warmed up over weeks by ramping volume slowly, and until it is warm your delivery can be worse than the shared pool you left. It only pays off at high, steady volume, the sort that keeps an IP busy enough for mailbox providers to trust it. Below that, a provider's shared pool, especially a transactional-only one like Postmark's, usually delivers better than a cold dedicated IP ever will, which is exactly why Postmark will not sell you one under 300,000 emails a month. So a dedicated IP is a scale decision, not a default: price it in only when your volume is high and steady enough to keep it warm, and lean on the shared pool until then.

So which should you pick

• You have engineers and real volume and want the lowest bill: Amazon SES. You accept building the templates, dashboard and deliverability tooling around a bare API in exchange for the cheapest send by a wide margin.
• Deliverability of critical mail matters more than cost: Postmark. You pay a premium per email for separated streams and a reputation built around receipts and resets arriving fast.
• You want a great API and dashboard with little setup: Resend. It costs more per email than SES and far less effort, and stays cheap at volume compared with Postmark.
• You already send marketing email and want transactional in the same place: Brevo, which runs both from one account with a generous free transactional tier.
• You are migrating off SendGrid's old free plan: any of the above, but Resend and Brevo are the closest replacements for a free-to-low-cost on-ramp, since SendGrid's free tier is gone.

Do not budget it from your newsletter

The mistake that this whole comparison guards against is pricing transactional email off your marketing email plan, or the reverse. They run on different meters: marketing bills by contacts stored, transactional bills by messages sent, and a plan that is cheap on one can be wrong on the other. If deliverability rather than price is your worry, our guide on why your cold email lands in spam covers the authentication and reputation work that decides whether any of these providers actually reaches the inbox. And to price the marketing side properly, where the contacts-versus-sends split is the whole game, the email platform cost calculator models it directly so you can see which pricing model fits your ratio before you commit.