Amazon Web Services“Listed in their tool stack on Starter Story (email)”
Transactional EmailMaker says so +2 · source ↗
Postmark
Transactional email service that keeps transactional and bulk mail on separate streams.
Works with AI agents:llms.txtAsk your AI about this, with this page as the source:ChatGPT ↗Claude ↗Perplexity ↗
Postmark is a hosted service for application email such as password resets, receipts and notifications, with a separate path for broadcast mail like newsletters and product announcements. It is part of ActiveCampaign.
An account holds "servers": each has its own API token, statistics, templates and inbound address, so teams typically use one per app or per environment. Inside a server, mail goes into message streams, either transactional or broadcast, and the two never share IP ranges. You send over a JSON-only REST API or SMTP and pick the stream per message. Official libraries cover TypeScript/Node.js, Python, Ruby and Rails, .NET, Java and PHP, plus a CLI.
Useful for a small team: hosted templates with an editor; inbound processing that turns incoming mail into JSON posted to your webhook (on Pro and above); 45 days of full message content for troubleshooting by default, adjustable from 7 to 365 days; and a batch endpoint taking up to 500 messages per call.
Every new account is reviewed by hand, and until it's approved you can only send to domains you've verified. Content rules are strict: bulk mail must go through a broadcast stream, and accounts are expected to stay under 0.1% spam complaints and 10% bounces. Data is hosted in the US (a Chicago-area data center and AWS) with no EU servers planned, and Postmark itself hasn't undergone a SOC audit.
Where it fits
How Postmark itself is built
2 tools, from its own code, website and Product Hunt page.
Who uses it
615 makers' products, each linked to the source that shows it, and 5 open-source projects that declare it in their code.
The maker says so 38Subprocessor list 14Seen on the website 602Declared in code 9How evidence is collected →
“Listed in their tool stack on Starter Story (email)”
Transactional EmailMaker says so +2 · source ↗
Balsamiq WireframesLow-fidelity wireframing tool for sketching UI mockups quickly, available as a cloud or…“Listed in their tool stack on Starter Story (email)”
Transactional EmailMaker says so +2 · source ↗“It’s built with Remix , Tailwind CSS and Prisma , and integrates nicely with Stripe for payments, Postmark for emails and Zapier for Webhooks.”
Transactional EmailMaker says so +1 · source ↗“Listed in their tool stack on Starter Story (span)”
Transactional EmailMaker says so +1 · source ↗
THEO GrowthPositioning Intelligence for brand strategists“Postmark handles all our critical user communications. We couldn't do without it.”
Transactional EmailMaker says so +1 · source ↗“Listed in their tool stack on Starter Story (email)”
Transactional EmailMaker says so +1 · source ↗
Hello InboxMaximize inbox placement for email marketing campaigns“We chose Postmark for it's simplicity, good deliverability and ease of integration.”
Transactional EmailMaker says so +1 · source ↗“Listed in their tool stack on Starter Story (email)”
Transactional EmailMaker says so +1 · source ↗“Listed in their tool stack on Starter Story”
Transactional EmailMaker says so +1 · source ↗“Sendgrid to send emails but considering a migration to Postmark .”
Transactional EmailMaker says so +1 · source ↗“Listed in their tool stack on Starter Story (email)”
Transactional EmailMaker says so +1 · source ↗
DecodedAI assistants you can email for deep research and more“Postmark makes it easy to build with the email protocol. It was the only platform that fully met our email infrastructure needs.”
Transactional EmailMaker says so +1 · source ↗“Postmark has been easy and very affordable to use, largely thanks to their step-by-step guides and great support.”
Transactional EmailMaker says so +1 · source ↗
PodSnap.AIget a summary email for every new podcast episode“Once you get familiar with Postmark's layouts and templates, the service is great for quickly creating email templates and sending them out using their simple API. The UI is simple and intuitive.”
Transactional EmailMaker says so +1 · source ↗
Reach from SalesStream.aiSimplest Email & SMS campaign builder for business owners“Love Postmark! It's our go-to tool for transactional in-app email”
Transactional EmailMaker says so +1 · source ↗“For emails I use ConvertKit to manage my newsletter subscriptions, and Postmark for transactional emails.”
Transactional EmailMaker says so +1 · source ↗
Plybuilding features into your existing stack, with no-code“We use Postmark not only for our emails, but also to power Ply's built-in dynamic email capabilities. It's reliable, well documented and most of all - comes with awesome human support.”
Transactional EmailMaker says so +1 · source ↗“Listed in their tool stack on Starter Story (email)”
Transactional EmailMaker says so +1 · source ↗
BlogBowlKeyword‑driven AI articles auto‑posted to your blog“We use Postmark to send emails and manage newsletters directly from BlogBowl. Big thanks to Postmark for their reliable API and top-notch deliverability, which makes sure your newsletters actually reach your subscribers! We considered alternatives like AWS SES and Mailgun, but Postmark felt like a next-level solution—super easy to integrate and consistently reliable.”
Transactional EmailMaker says so +1 · source ↗
Invite.socialFree Classy Customizable Event RSVPs & Invitations“Postmark is the most reliable email sending tool, hands down. Use it with all of my products.”
Transactional EmailMaker says so +1 · source ↗“We use some integrations that nowadays have become basic for our business like Postmark (for transactional emails) or Sift (to detect users with not very good intentions).”
Transactional EmailMaker says so +1 · source ↗
BlogMakerBlogging platform for SEO that runs in a subdirectory of a company's own domain, with a…“All transactional and broadcast messages from blogstatic go through Postmark. An incredible team with an incredible group of humans behind it.”
Transactional EmailMaker says so +1 · source ↗Open source: a project that declares Postmark as a dependency in its public code — verifiable, but not necessarily a live product.
What makers say
25 makers on why they use Postmark, in their own words on Product Hunt.
We use Postmark to send emails and manage newsletters directly from BlogBowl. Big thanks to Postmark for their reliable API and top-notch deliverability, which makes sure your newsletters actually reach your subscribers! We considered alternatives like AWS SES and Mailgun, but Postmark felt like a next-level solution—super easy to integrate and consistently reliable.
BlogBowlSep 2026 ↗We use Postmark to send emails and manage newsletters directly from BlogBowl. Big thanks to Postmark for their reliable API and top-notch deliverability, which makes sure your newsletters actually reach your subscribers! We considered alternatives like AWS SES and Mailgun, but Postmark felt like a next-level solution—super easy to integrate and consistently reliable.
BlogBowlOct 2025 ↗Once you get familiar with Postmark's layouts and templates, the service is great for quickly creating email templates and sending them out using their simple API. The UI is simple and intuitive.
PodSnap.AISep 2026 ↗We use Postmark not only for our emails, but also to power Ply's built-in dynamic email capabilities. It's reliable, well documented and most of all - comes with awesome human support.
PlySep 2026 ↗We use some integrations that nowadays have become basic for our business like Postmark (for transactional emails) or Sift (to detect users with not very good intentions).
Loved and watch-outs
Themes that recur in makers' words and Hacker News comments, each linked to what it summarises, with how Product Hunt tags its reviews.
Most loved
- Its reputation for transactional mail gives strong inbox deliverability. PHHNHN 2
- The API is simple enough to use with plain curl, and templates and layouts speed up building emails. PHHNHN 2
- Inbound email processing is built in, so apps can receive and parse replies. PHHNHN 2
- It is affordable, transparent and backed by good docs and responsive human support. PHHNHN 2
On Product Hunt 5.0★ · 22 reviews
reliable email delivery 5fast performance 3human support 3transactional email 3
Read the reviews on Product Hunt ↗Who switches
Public pull requests on GitHub since Oct 2024 whose title says "X to Y" — real code changes moving a project from one tool to another, by developers in general. Open a row to see the pull requests.
Resend → Postmark6 PRs
- refactor(backend): move transactional email from Resend to PostmarkPomodoso/pomodoso · 2026-08-28
- Migrate assessment email routes from Resend to PostmarkRussellLack/ecm-dev-nextjs · 2026-08-21
- Replace notification email delivery from Resend to Postmarkbrosenbauer-m/LiAIson · 2026-06-17
- Rename outbound email provider references from Resend to Postmarkbrosenbauer-m/LiAIson · 2026-06-17
- Swap email-to-task webhook from Resend to Postmarkyoungfonz/pulsepro.work · 2026-04-18
- feat(email): migrate from Resend to Postmarkmasumi-network/sokosumi · 2025-09-24
SendGrid → Postmark6 PRs
- fix: migrate from SendGrid to Postmark (v0.3.23)nomadkaraoke/karaoke-decide · 2026-05-18
- Update email service from SendGrid to Postmark and remove related doc…Webcap/wiznote · 2025-11-04
- Release sendgrid to postmark swapClaudia413/tjp-website · 2025-08-19
- swap sendgrid to postmarkClaudia413/tjp-website · 2025-08-09
- Switch from SendGrid to Postmarkdanstewart/log-my-time · 2025-05-28
- [sendgrid] back to postmarkinstantdb/instant · 2025-04-03
Postmark → Resend3 PRs
- chore(mail): switch SMTP defaults from Postmark to Resendjustuseapen/baltimore_ai · 2026-05-12
- feat(web): swap inbox vendor from Postmark to Resend Inbound (HMAC + vendor consolidation)Mikecranesync/MIRA · 2026-04-25
- Switch mailer from Postmark to Resend SMTPjmanian/nba-playoff-pool · 2026-04-17
Alternatives to Postmark
All alternatives by situation →ResendA modern developer API with email templates written as React components.Compare with Postmark →
Mailgun
Amazon SES
Nodemailer
useSendOn Product Hunt, people weigh it against: Resend, Loops, Mailgun, Plunk.
Questions makers ask about Postmark
Can I email my users right after signing up?
Only addresses on domains you've verified, until your account passes a manual review. Reviews finish within 24 hours on weekdays; meanwhile you can build templates, inbound handling and webhooks, and send test mail to [email protected]. source ↗
Can I send newsletters and marketing email through it?
Yes, through broadcast message streams, which run on infrastructure kept apart from your transactional mail so the two never mix. source ↗
What kind of email is not allowed?
Bulk mail sent through a transactional stream, and lists that produce high complaint or bounce rates. Postmark asks you to keep complaints under 0.1% and bounces under 10%, and not to use it to clean old lists. source ↗
Where is my data stored? Is there an EU region?
Primary data and servers are in a data center outside Chicago and on AWS, and there are no plans to add EU servers. A DPA and a list of sub-processors are provided for GDPR. source ↗
Is Postmark SOC 2 certified?
Postmark itself hasn't had a SOC audit. Its data center is SOC 2 Type 2 accredited, and Postmark can share that report. source ↗
Are webhook requests signed?
No. Postmark recommends protecting the endpoint with HTTP basic authentication in the webhook URL and allowing only its published IP ranges through your firewall. source ↗
How hard is it to move over from SendGrid?
There's a migration guide that maps SendGrid concepts, API fields and webhooks to Postmark's. Differences to plan for are the separate message streams, JSON-only APIs and no reseller API. source ↗
Is Postmark free?
Yes — there is a free tier a small product can run on; paid use starts at $15/mo. source ↗
Is Postmark open source or self-hostable?
Not open source, and hosted only.
Can AI coding agents work with Postmark?
It serves an llms.txt docs index.
Who uses Postmark?
615 makers' products we track, each with a source, and 5 open-source projects declare it in their code. source ↗