Postmark and Notix both start paid plans at $15 a month. Postmark includes 10,000 emails at that price and charges $1.80 per extra 1,000; Notix includes 50,000 and meters the rest on the same invoice. Notix also puts marketing mail, an OTP API and a pre-send deliverability check in the same account, and its free plan is 5,000 a month rather than 100. Teams whose first priority is Postmark's own transactional-only infrastructure and its separate message streams should stay; that is what they are paying for, and Notix does not contest it. Teams paying for volume should read on.
Postmark's pricing page puts 10,000 emails on the $15 Basic plan and $1.80 on every extra thousand. A product sending 30,000 receipts and notifications a month is paying $51, and the number keeps climbing with growth. The developer plan above it is 100 emails a month, which is a test allowance, not a free tier.
Postmark built its reputation on refusing bulk marketing mail, and its home page still leads with transactional delivery. That is a virtue for deliverability and a cost for a team that also needs a newsletter, a contact book and an unsubscribe list: those live somewhere else, with a second bill and a second suppression list to keep in sync.
Postmark sends the message. Generating a one-time code, storing it, expiring it and checking the user's answer is code you write and host, and there is no call that tells you before a send whether the message is likely to land. Sign-in flows and password resets end up with the same hand-built layer on every project.
Every Postmark figure was read from Postmark's own pages on 2026-09-13; the date sits under the table. If a number has changed since, the page is wrong and we would like to know.
| Criterion | Postmark | Notix |
|---|---|---|
| Free tier | 100 emails a month on the developer plan | 5,000 emails a month, 200 a day, no card, no end date |
| Entry paid plan | Basic $15 a month | Pro $15 a month |
| Included on that plan | 10,000 emails a month, then $1.80 per extra 1,000 | 50,000 emails, usage past that metered on the same invoice |
| SMTP relay | Yes, on every plan | Yes, on every plan |
| SDKs | Node, Python, Ruby, PHP, .NET, and a documented cURL surface | TypeScript, Python, Go, PHP |
| Webhooks | Yes | Yes, signed, for email, contact and domain events |
| OTP / verification API | No | Yes, email and SMS codes |
| Deliverability check before sending | No | Yes, a pre-send check API |
| Billing outside USD | USD by card | USD by card; naira and shillings from a prepaid wallet |
| SLA | Not stated on the pricing page | 99.9% on Pro, credits on the pricing page |
| Prices and limits read from the vendors' own pages: postmarkapp.com on 2026-09-13. Notix figures are from its own pricing page. | ||
Postmark runs its own sending infrastructure and manages its reputation as a transactional-only sender, and it publishes how long messages take to reach the major inboxes. This page does not contest any of that; if you chose Postmark for it, you chose well. Its message streams keep transactional and broadcast mail on separate reputations inside one account, which Notix does not offer. Its official libraries cover Node, Python, Ruby, PHP and .NET, and its documentation has had years of polish. Postmark has also been owned by ActiveCampaign since May 2022, which for some teams is stability and for others a reason to look around.
Both send through a JSON API and over SMTP on every plan, both deliver webhooks for delivery, bounce and complaint events, and both let you verify a domain with SPF, DKIM and DMARC. For a plain transactional send the two calls carry the same fields under different names; the migration section below shows the whole change.
Pro includes 50,000 emails for $15. Past that, usage is metered on the same invoice at the rate on the pricing page; there is no next tier to move to.
Receipts and campaigns from one account, one email API, one contact book, and one suppression list that both kinds of mail respect.
One call sends a code by email or SMS, one call checks it. Expiry, attempts and rate limits are handled server-side. See OTP email.
Post the message and get back a spam score, missing headers and domain problems before a recipient sees it. Part of the transactional email API.
Pro carries a 99.9% monthly uptime commitment, with the credit schedule written on the pricing page.
The send call carries the same fields under lowercase names, and there is no message stream to name. Swap the client, swap the key, verify your domain, and the rest of your code stays as it is.
import { ServerClient } from "postmark";
const client = new ServerClient(process.env.POSTMARK_SERVER_TOKEN);
await client.sendEmail({
From: "receipts@acme.com",
To: "customer@example.com",
Subject: "Your receipt",
HtmlBody: "<p>Thanks for your order.</p>",
MessageStream: "outbound",
});
import { Notix } from "notix-js";
const notix = new Notix(process.env.NOTIX_API_KEY);
const { data, error } = await notix.emails.send({
from: "receipts@acme.com",
to: "customer@example.com",
subject: "Your receipt",
html: "<p>Thanks for your order.</p>",
});
# Before
SMTP_HOST=smtp.postmarkapp.com
SMTP_PORT=587
SMTP_USER=<server API token>
SMTP_PASS=<server API token>
# After
SMTP_HOST=smtp.usenotix.dev
SMTP_PORT=465
SMTP_USER=notix
SMTP_PASS=<your Notix API key>
Add the SPF, DKIM and DMARC records Notix gives you. They sit beside Postmark's records, so both services can send while you switch. The quickstart walks through it.
Replace the postmark package with notix-js and put an API key in your environment; the MessageStream field simply goes. If you send over SMTP, change the host and credentials as shown above; the SMTP relay takes the same message your mailer already builds, on port 465 or 587.
Export the addresses Postmark has recorded as bounced, complained or unsubscribed and upload them under Suppressions in the dashboard, one address per line, so the first sends from Notix never reach an address that has already said no. Webhook URLs move last, once traffic has.
| Emails a month | Postmark | Notix |
|---|---|---|
| 10,000 | Basic, $15 (the developer plan stops at 100) | Pro, $15 (Free stops at 5,000) |
| 50,000 | Basic, $15 plus 40 × $1.80: about $87 | Pro, $15 |
| 100,000 | Basic, $15 plus 90 × $1.80: about $177, or a larger plan; see postmarkapp.com/pricing | Pro, $15 plus the 50,000 above the allowance, metered on the same invoice |
At 10,000 emails the two cost the same. At 50,000 the overage on Postmark's Basic plan takes it to roughly $87 against Notix's $15; Postmark's larger plans may price that volume differently, so check its pricing page for your exact number. At 100,000 Notix keeps you on Pro and adds the overage to the same invoice at the per-unit rate on the pricing page, where you can run the estimate for your own volume. Postmark prices read on 2026-09-13.
Postmark bills in US dollars by card. Teams in Nigeria and Kenya fund a Notix wallet in naira or shillings through local payment methods and Pro is charged from that balance each month, so nobody needs a dollar card that clears international charges. The free plan is the same everywhere, and the local price per email is on the pricing page when you open it from either country.
A free plan with no card, and Pro at $15 a month for 50,000 emails. Only sent volume is metered.
AlternativesSame free tier shape, $5 a month less at 50,000 emails, plus OTP and deliverability APIs and naira or shilling billing.
AlternativesSame $15 entry, 50,000 emails instead of 10,000, and a suppression list shared across transactional and marketing.
ProductOTPs, receipts and alerts with idempotency keys, a deliverability pre-check and a shared suppression list.
ProductOne JSON API for transactional and marketing email: send, batch, schedule, webhooks, typed SDKs.
AlternativesHonest switch pages for the email APIs people move away from, with the vendor's own numbers and read dates.
5,000 emails a month on Free. When you outgrow it, Pro is $15 for 50,000, payable by card or from a naira or shilling wallet.