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Email Marketing Comparison

Mailgun vs. Postmark

At a glance

At a glance

Mailgun

Best for

Best for engineering teams sending at high volume that need an API and SMTP relay, with the option of an EU data centre.

  • Freelancers
  • Small and mid-sized
  • Enterprise

Postmark

Best for

Best for product and engineering teams whose transactional email has to arrive, and who want promotional sending kept on separate infrastructure.

  • Freelancers
  • Small and mid-sized
  • Enterprise

Cataleo does not name a winner. Both statements come from the vendors themselves.

Full Comparison

Criterion Mailgun Postmark
Starting price Free tier; Basic from $15 / month Basic $15 per month for 10,000 emails, Foundation $35 for 50,000 and Scale $90 for 100,000, then Enterprise on request. Overage is $1.80 per 1,000 on Basic and Foundation and $1.10 on Scale. Foundation and Scale are free for the first month. Free tier; Basic from $15 / month All three paid plans start at 10,000 emails per month and differ mainly by overage rate: Basic $15 at $1.80 per 1,000 extra emails, Pro $16.50 at $1.30, Platform $18 at $1.20.
Free trial Free tier: 100 emails per day Free tier: 100 emails per month, no overages permitted, never expires
API Yes, RESTful email API and SMTP relay, with official SDKs for Python, Ruby, PHP, Java, C#, Node.js and Go Yes, REST API and an SMTP service, with official libraries for TypeScript, Node.js, Python, Ruby, PHP, .NET and Java
Hosting Cloud (SaaS), with data centres in the US and the EU Cloud (SaaS)
Campaign types Transactional and bulk sending over the RESTful API or the SMTP relay, batch sending of up to 1,000 personalised messages per call, scheduled messages, and inbound routing that parses received mail into UTF-8 JSON Transactional and broadcast email on separate Message Streams, plus inbound email processing that delivers received mail to your application
Automation and journeys No journey builder. Sends are triggered by your own application, with message scheduling and Send Time Optimization placing individual messages when a recipient is most likely to engage. No journey or automation builder. Sends are triggered by your own application over the API or SMTP, and delivery events are pushed back out through webhooks.
Segmentation and personalisation Per-recipient personalisation through batch sending, which substitutes recipient variables for up to 1,000 addresses in a single API call; mailing lists are documented in the user manual. No stored audiences or segment builder. Recipients and their personalisation values are supplied per request, while Postmark maintains bounce state and suppression lists.
Templates and editor Reusable templates, documented in the user manual alongside mailing lists, batch sending and scheduling; there is no drag-and-drop campaign designer in the sending product Reusable email templates with variable substitution, managed in the dashboard or over the Templates API; there is no drag-and-drop campaign designer
Deliverability and testing Authentication covers SPF, DKIM, DMARC and BIMI, with suppression management and an email validation API. Deeper tooling sits in Mailgun Optimize, priced separately: inbox placement testing down to the tab or folder, blocklist and spam trap monitoring with Google Postmaster Tools and Microsoft SNDS integration, preview rendering on 100+ devices and clients, and deliverability consulting. One dedicated IP is included from Foundation; extra IPs are $59 per month. Message Streams keep promotional sending on infrastructure separate from transactional mail. Message data is retained for 45 days, extendable to 365 days on Pro and Platform from $5 per month. Dedicated IPs start at $50 per month per IP and DMARC monitoring at $14 per month per domain.
Ecommerce and CRM data No store or CRM data model of its own; orders and customer records stay in the system they come from. The integrations directory connects Salesforce, Salesforce Agentforce Marketing, HubSpot, SAP S/4HANA Private Cloud Edition and WordPress, whose free Mailgun plugin also carries the mail from plugins running on it such as WooCommerce. Shopify runs through Zapier rather than a Shopify app, triggering on events such as a new order to send a message or add the customer to a Mailgun list. No built-in ecommerce or CRM data sync. Contact data stays in your own application, which supplies it with each send.
Integrations and API Yes, RESTful email API and SMTP relay, plus an SMTP API for finer sending control, webhooks for real-time event data and an email validation API. Official SDKs for Python, Ruby, PHP, Java, C#, Node.js and Go. Yes, REST API with separate server and account tokens over TLS, plus an SMTP service with IP allowlisting. Endpoints cover email, batch sending, templates, bounces, inbound, message streams and suppressions. Official libraries for TypeScript, Node.js, Python, Ruby, Rails, PHP, .NET and Java, plus a WordPress plugin; community libraries add Go, Elixir, Laravel and Scala.
Deployment Cloud (SaaS), Browser-based Cloud (SaaS), Browser-based
Support more entries Email helpdesk, Phone, Chat Email helpdesk
Onboarding Documentation and knowledge base Documentation and knowledge base
Company size Freelancers, Small and mid-sized, Enterprise Freelancers, Small and mid-sized, Enterprise
Integrations more entries Salesforce, HubSpot, Shopify, WordPress, WooCommerce, SAP S/4HANA, Zapier, Make, n8n, Pipedream, Workato, Slack, Asana, Google Analytics, Datadog, Splunk, Heroku, GitHub Actions, Replit, Lovable Zapier, Slack, Stripe, Datadog, Supabase, Netlify, Bubble, Craft CMS, WP Mail SMTP, Gravity Forms, ActiveCampaign, Customer.io, Mailcoach, Stripo, Tabular, SureTriggers

Compare more tools

Row where the values differ The small markers point at the lower number, the longer list or the stated feature. They describe the data, they are not a verdict.

The short version

Key Differences

  • Free trial Mailgun Free tier: 100 emails per day Postmark Free tier: 100 emails per month, no overages permitted, never expires
  • Hosting Mailgun Cloud (SaaS), with data centres in the US and the EU Postmark Cloud (SaaS)
  • Support Mailgun Email helpdesk, Phone, Chat Postmark Email helpdesk
  • API Mailgun Yes, RESTful email API and SMTP relay, with official SDKs for Python, Ruby, PHP, Java, C#, Node.js and Go Postmark Yes, REST API and an SMTP service, with official libraries for TypeScript, Node.js, Python, Ruby, PHP, .NET and Java
  • Campaign types Mailgun Transactional and bulk sending over the RESTful API or the SMTP relay, batch sending of up to 1,000 personalised messages per call, scheduled messages, and inbound routing that parses received mail into UTF-8 JSON Postmark Transactional and broadcast email on separate Message Streams, plus inbound email processing that delivers received mail to your application

Every line is one datapoint from the table above, picked automatically. Nothing here is written text.

The trade-offs

Strengths and Limitations

Mailgun

Strengths

  • RESTful API and SMTP relay as two routes into the same sending infrastructure
  • Batch sending of up to 1,000 fully personalised messages in one API call
  • Data centres in both the US and the EU
  • Official SDKs for seven languages
  • Inbound routing parses received mail into UTF-8 JSON for other systems

Limitations

  • Log retention is one day on Free and Basic and five days on Foundation
  • Deliverability tooling sits in Mailgun Optimize and is priced separately from sending
  • No journey or campaign builder; marketing automation lives in the sibling product Mailjet
  • Additional dedicated IPs cost $59 per month each
  • Phone and chat support require the Scale plan
  • Messages sent in test mode are still charged

Postmark

Strengths

  • Message Streams keep promotional sending on infrastructure separate from transactional mail
  • Standing free tier of 100 emails a month that never expires
  • Official client libraries for eight languages plus a WordPress plugin
  • Inbound email processing on the Pro and Platform plans
  • Message data retention extendable from 45 days to 365 days on Pro and Platform

Limitations

  • No automation, journey builder or stored audiences
  • Inbound email is not included on the Free and Basic plans
  • Dedicated IPs, extended retention and DMARC monitoring are priced as add-ons
  • The free tier permits no overage, so sending stops at 100 emails
  • All three paid plans start at the same 10,000 emails, so the choice is really about overage rate

Plans

Pricing

Mailgun

  • Free $0 100 emails per day, with one day of log and message retention and knowledge centre support only.
  • Basic $15 Per month for 10,000 emails, overage $1.80 per 1,000. One day of log and message retention, ticket support.
  • Foundation $35 Per month for 50,000 emails, free for the first month, overage $1.80 per 1,000. Five days of log retention and one dedicated IP included.
  • Scale $90 Per month for 100,000 emails, free for the first month, overage $1.10 per 1,000. 30 days of log retention, up to seven days of message retention, phone and chat support.
  • Enterprise Not stated Custom pricing on request.
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Postmark

  • Free $0 100 emails per month with no overages permitted, and 45 days of data retention. Never expires.
  • Basic $15 Per month from 10,000 emails, overage $1.80 per 1,000. 45 days of data retention, no inbound email.
  • Pro $16.50 Per month from 10,000 emails, overage $1.30 per 1,000. Adds inbound email and data retention customisable to 365 days.
  • Platform $18 Per month from 10,000 emails, overage $1.20 per 1,000. Adds unlimited custom domains and message streams.
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What users say

Review Scores · opens after launch

Mailgun

Ease of use
Not rated yet
User interface
Not rated yet
Onboarding
Not rated yet
Support and service
Not rated yet
Value for money
Not rated yet
Features
Not rated yet

No reviews yet. Nothing has been published here yet, and no score is shown. How a review is checked before it appears is described below.

Postmark

Ease of use
Not rated yet
User interface
Not rated yet
Onboarding
Not rated yet
Support and service
Not rated yet
Value for money
Not rated yet
Features
Not rated yet

No reviews yet. Nothing has been published here yet, and no score is shown. How a review is checked before it appears is described below.

How we check reviews

Before sending, the author has to confirm three things: that they have used the product themselves, that they work neither for the vendor nor for a competitor, and that nobody is paying them for the review. We also ask whether the vendor invited them to write it. That answer is required, either answer is accepted, and it stays with the review.

Every review is read by a person before it appears. An email address is required and is confirmed: we send a link to it, and a review does not reach us until the author opens that link, so a review has a sender who was reachable at least once rather than being anonymous. Where what somebody writes needs backing, we ask them for evidence that they used the product, and a review that does not get it is not published. We publish positive and negative reviews alike, we pay nothing and offer nothing for a review, and we accept none that was bought or incentivised.

What we cannot do is verify a purchase. There is no shop here and no account, so whether the author really used the tool rests on their own declaration, on whatever we ask them for, and on the plausibility of what they write. We say so rather than implying a check that does not exist.

A vendor cannot buy a review, and cannot have one removed or changed because they dislike it. We remove or edit a review only if it breaks our rules or the law, for example a false statement of fact. Paid placement has no effect on which reviews appear or on any score.

Read the full version on our methodology page

Where this comes from

Where this comes from

Mailgun https://www.mailgun.com · checked against the official source on 2026-09-09

Postmark https://postmarkapp.com · checked against the official source on 2026-09-09

This table lists factual criteria taken from information the vendors publish themselves. For how we put it together, see the methodology.