Postmark vs Resend (2026): Pricing, Features, and Where SendHeron Fits

Postmark and Resend both send email from your code, but they price it very differently. Below about 12,800 emails a month Postmark's $15 Basic plan is the cheaper paid option. Above that Resend pulls ahead fast: $20 against $55 at 50,000 emails, and $35 against $115 at 100,000. What you get for Postmark's higher price is a product built around transactional email, 45 days of history and separate streams for transactional and broadcast mail. We build a third option, SendHeron, so this article also says where it fits and, just as plainly, where it does not.

Prices below are as of October 20, 2026, on monthly billing, from each vendor's own pricing page: Postmark and Resend in US dollars, SendHeron in euros. Prices change, so check before you decide.

What you will learn

• What each costs at 10,000, 50,000, 100,000 and 300,000 emails a month
• What the free plans really allow
• Where history, dedicated IPs, inbound email and SDKs differ
• How each one handles broadcasts, lists and automated sequences
• A plain recommendation per situation, including when SendHeron is the wrong pick

Quick comparison

Postmark pricing

Postmark prices by the emails you send and receive each month, on three paid plans that share the same volume tiers.

• Basic costs $15 for 10,000 emails, $55 for 50,000, $115 for 125,000 and $245 for 300,000. Extra emails cost $1.80 per 1,000 up to the 125,000 tier and $1.70 above it. It allows 5 sending domains and up to 4 users.
• Pro costs 10% more: $16.50 for 10,000, $60.50 for 50,000, $126.50 for 125,000 and $269.50 for 300,000, with extra emails from $1.30 down to $1.20 per 1,000. It adds inbound email processing, 10 sending domains, up to 6 users, and history you can extend up to 365 days.
• Platform costs $18 for 10,000, $66 for 50,000, $138 for 125,000 and $294 for 300,000, with extra emails at $1.20 or $1.15 per 1,000, and unlimited domains, servers, streams and users.

The free Developer plan sends 100 emails a month, never expires and allows no overages. Every plan keeps 45 days of history. Optional add-ons: dedicated IPs from $50 a month per IP, for Pro and above and only from 300,000 emails a month; longer history from $5 a month on Pro and above; and DMARC monitoring from $14 a month per domain.

Resend pricing

Resend prices transactional and marketing email separately.

Transactional email is anything sent through its /emails API, to any address. The Free plan sends 3,000 emails a month, at most 100 a day, from up to 3 domains. Pro costs $20 for 50,000 emails or $35 for 100,000, with 10 domains and no daily limit. Scale starts at $90 for 100,000 and runs $160 for 200,000, $350 for 500,000 and $650 for 1,000,000. Extra emails cost $0.90 per 1,000 on Pro and on Scale's 100,000 tier, falling to $0.46 per 1,000 on the largest Scale tier, but only if you switch on pay-as-you-go. Free, Pro and Scale keep 30 days of email and log data. A dedicated IP is a $30-a-month add-on, available on Scale to senders above 3,000 emails a day.

Marketing email goes through Broadcasts and is priced by stored contacts, not by emails sent: free up to 1,000 contacts, then $40 for 5,000, $80 for 10,000, $180 for 25,000 and $250 for 50,000. Automations, Resend's event-triggered sequences, include 10,000 runs a month; on paid plans each run beyond that costs $0.0015.

SendHeron pricing

SendHeron charges by subscribed contacts, with one monthly allowance of emails that marketing and transactional share. The full details are on the pricing page.

Only subscribed contacts count. Unsubscribed and bounced contacts are stored free, and sequences, tags and segments are unlimited on every plan. Transactional email keeps flowing even when the allowance is spent, up to 10% over the plan's pool. There is no free plan: every plan starts with a 7-day trial that takes a card at checkout, runs with reduced limits of 1,000 contacts and 5,000 sends, and converts to the plan you picked unless you cancel before it ends.

The pricing math

Transactional email only:

The 300,000 figure for Resend is our arithmetic from its listed rates. Below 3,000 emails a month Resend's free plan costs nothing, and between roughly 3,000 and 12,800 Postmark's $15 Basic plan is the cheaper paid option. Above that Resend costs well under half of what Postmark does up to 100,000 emails, and the gap narrows at higher volumes. With a dedicated IP at 300,000 emails, Postmark needs Pro at $269.50 plus $50 for the IP, $319.50, against $270 on Resend Scale ($160 for 200,000 plus 100,000 at $0.80 per 1,000, plus $30 for the IP).

Now a SaaS that sends both kinds of email: lifecycle sequences to 5,000 contacts plus 25,000 transactional emails a month.

• Postmark: $55 on Basic if everything fits in 50,000 emails a month. Postmark sends what your app tells it to send, so the contact list and the sequence logic stay in your own code.
• Resend: $20 on Pro if your app runs the sequences and sends every email through the API, which Resend allows for individual marketing emails. Storing the 5,000 contacts in Resend for Broadcasts adds the $40 Marketing plan, $60 in total, and Automations include 10,000 runs a month.
• SendHeron: €19 on Starter, which covers up to 10,000 contacts and 50,000 emails across both kinds.

Feature comparison

API, SDKs and templates

Both offer a REST API and SMTP. Postmark has official libraries for TypeScript, Node.js, Python, Ruby, Rails, .NET, Java and PHP, and its templates use the Mustachio language, with responsive templates and an editor. Resend has official SDKs for Node.js, Python, PHP, Ruby, Go, Rust, Java and .NET, plus a community library for Elixir, and supports React Email, so templates can be written as React components. Resend's API allows 10 requests a second per team by default, and one batch request sends up to 100 emails.

Transactional and broadcast mail

Postmark separates the two with Message Streams: transactional and broadcast email go through different streams, which Postmark says protects both kinds of mail. Its own FAQ is clear about the limit: you keep your main email lists outside Postmark, and if your sending is mostly marketing promotion, other tools may fit better. Resend splits them by API: the /emails API counts against the transactional quota, while Broadcasts go to contacts you store in Resend and are priced by the number of contacts.

History and logs

Postmark keeps 45 days of activity on every plan, and Pro and above can extend it up to 365 days with an add-on from $5 a month. Resend keeps 30 days of email and log data on Free, Pro and Scale. If you investigate delivery problems weeks later, Postmark gives you more room.

Deliverability tools

Both authenticate your domain with SPF and DKIM, work with DMARC and suppress bounced addresses automatically. Dedicated IPs differ in price and threshold: Postmark's start at $50 a month per IP on Pro and above, only for senders of 300,000 emails a month or more; Resend's is a $30-a-month add-on on Scale for senders above 3,000 emails a day. Postmark also sells DMARC monitoring from $14 a month per domain. Whichever you pick, a free deliverability test shows whether your domain's records are in place.

Inbound email

Postmark processes inbound email on every plan except Basic, the free Developer plan included, turning each message into JSON posted to your webhook; received emails count toward the monthly volume. Resend also receives inbound email, counted against the same quota as sent mail; its Inboxes feature is still in early access. SendHeron does not receive email.

Teams and data

Postmark allows up to 4 users on Basic, 6 on Pro and unlimited users on Platform. Resend sends from four regions, North Virginia, Ireland, São Paulo and Tokyo, and its documentation says account data, logs and API records are stored in the United States whichever region you send from. Postmark's privacy policy says data may be transferred to ActiveCampaign locations including the United States. SendHeron is an EU company and stores contact data in Europe.

Lifecycle sequences

Postmark leaves sequences to your app. Resend offers Automations, event-triggered sequences such as welcome and trial emails. SendHeron is built around them: you build sequences in a visual editor from the tags and events your app sets, and its AI setup reads your website and drafts a welcome, trial, win-back and cancel-save suite for you to approve.

Who should use what

Choose Postmark if

• You send under about 12,800 emails a month and want the cheapest paid plan
• You want 45 days of history, with the option of up to a year
• You send newsletters from your own app and want them on a separate stream from transactional mail
• You want DMARC monitoring from the same vendor

Choose Resend if

• You send more than about 12,800 emails a month and want the lower price
• You want a free plan of 3,000 emails a month while you build
• You write templates in React
• You want broadcasts and automated sequences in the same product as your API

Choose SendHeron if

• You run a SaaS and want lifecycle sequences and transactional email from one API and one allowance
• You would rather approve a drafted lifecycle suite than build one from a blank canvas
• You want to pay for subscribed contacts, not for every product email on a separate meter

SendHeron is the wrong pick if you need SMTP, inbound email, a dedicated IP, an official SDK in a language other than Node.js, or more than 500,000 emails a month. Postmark or Resend fits those better today.

We also compare Resend vs SendGrid and Mailgun vs Resend, and three lifecycle pairs in Customer.io vs Mailchimp, Loops vs Customer.io and Customer.io vs Intercom.

Frequently asked questions

Is Resend cheaper than Postmark?

Above about 12,800 emails a month, yes. At 50,000 emails Resend Pro costs $20 against $55 for Postmark Basic, at 100,000 it is $35 against $115, and at 300,000 about $215 against $245. Below that, Postmark's $15 Basic plan is the cheaper paid option, and Resend's free plan covers up to 3,000 emails a month.

Does Postmark have a free plan?

Yes. The Developer plan sends 100 emails a month, never expires and allows no overages. It is meant for testing an integration.

Can Postmark send newsletters?

Yes, through a broadcast message stream kept apart from your transactional mail. You manage the list itself outside Postmark, and Postmark says other tools may suit senders whose email is mostly marketing promotion.

How long does each one keep email history?

Postmark keeps 45 days on every plan and lets Pro and above extend it up to 365 days as a paid add-on. Resend keeps 30 days of email and log data on Free, Pro and Scale.

Is Resend vs Postmark a different question from Postmark vs Resend?

No. It is the same comparison in the other order, and everything above applies.

Start with the one that fits

If you send a few thousand transactional emails a month and want long history and separate streams, start with Postmark. If you send more, want a generous free plan, React templates or broadcasts and automations in one product, start with Resend. If you run a SaaS and want lifecycle sequences and transactional email on one bill, start a 7-day trial of SendHeron. It takes a card; cancel before it ends and you will not be charged.