The Stalwart Mail Server Insider’s Guide
Everything we know about Stalwart Mail Server in one document: what it costs, its grades, getting a refund, getting help and what else to look at. Read it here, or keep a copy.
Stalwart Mail Server
The Insider’s Guide
Open-source mail and collaboration server written in Rust
Every plan, grade, refund rule and rival among email apps, read from Stalwart Mail Server’s own pages.
Made by Stalwart Labs · checked Nov 13, 2026 · toolgpa.com
Contents
- 01WelcomeWhat it is, who it suits, its grades and the ten things to know first
- 02What it costsEvery plan, the free plan, ways to pay less and how prices have moved
- 03What it doesIts main features, where it runs, what it works with and who makes it
- 04Where it standsIts grades against its category, and whether to keep it or make your own
- 05The alternativesThe tools it is most often weighed against, side by side
- 06Quick answersThe questions people ask about it, each answered in a line or two
- 07About ToolGPAWho made this guide, what else is on the site, and how to cite it
ToolGPA put this guide together from Stalwart Mail Server’s own pages, its app-store listings and our grades. Every fact in it is on Stalwart Mail Server’s page too, where it is kept up to date. Checked Nov 13, 2026.
Part 01 · Overview
Welcome
What it is, who it suits, its grades and the ten things to know first
2.2
GPA, above 29 of the 122 other email apps we grade
Stalwart is a single server that handles email, calendars, contacts and shared files, with spam and phishing filtering built in. It speaks JMAP, IMAP, POP3, SMTP, CalDAV, CardDAV and WebDAV. A free Community edition is licensed under AGPL-3.0, and a paid Enterprise edition adds multi-tenancy, branding and archiving.
To get you started, here are 9 things to know about Stalwart Mail Server, taken from its own pages and our grades.
You install, configure and update the server yourself, in either edition.
- 1
Best for a mail and collaboration server in Rust
Stalwart is an open-source mail and collaboration server.
- 2
Paid plans start at $0.20 a month when paid by the year
As its pricing page puts it: $2.40 per mailbox / year, billed annually (25-mailbox minimum).
- 3
There is a free plan
Community edition: the full mail server under AGPL-3.0, free to run on your own infrastructure.
- 4
It runs on Web
Web.
- 5
Mail and collaboration in one server
JMAP, IMAP and POP3 for mail, SMTP for delivery, plus calendars, contacts and file storage over CalDAV, CardDAV and WebDAV.
- 6
Built-in spam and phishing filtering
A statistical classifier, public blocklists, sender reputation and AI-driven analysis run inside the server.
- 7
Sender authentication and transport security
Handles DKIM, SPF, DMARC and ARC, plus DANE, MTA-STS and TLS reporting, with automatic certificate renewal over ACME.
- 8
A 2.2 GPA, above 29 of 122
That is against the other email apps we grade, on value, the free plan, features, ease of use and platforms.
- 9
Keep it
To replace Stalwart Mail Server you would be making an email client: sending, receiving, threading and searching years of mail. That is not a weekend's work, with an AI app builder or without one.
Stalwart Mail Server at a glance
- Pricing
- Free plan, from $2.40 per mailbox / year, billed annually (25-mailbox minimum)
- Free plan
- Yes
- Free trial
- 30-day trial of the Enterprise edition with full access to Enterprise features.
- Runs on
- Web
- Made by
- Stalwart Labs
- Category
- Email Apps
- Our grade
- 2.2 GPA, fair
The report card
Best for a mail and collaboration server in Rust
Stalwart is an open-source mail and collaboration server. The Community edition is free to run yourself, and Enterprise costs $2.40 a mailbox a year with a 25-mailbox minimum. You run and update it either way, and the hosted service is not out until 2027.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | C | Community is free if you host it. Enterprise is $2.40 a mailbox a year, but you pay for at least 25 mailboxes, which is $60 a year. |
| Free plan and trial | B | The full server is free to run under the AGPL, plus a 30-day trial of Enterprise. You need your own server. |
| Features | B | Mail and collaboration in one server, with spam filtering, encryption at rest and clustering. The listing shows no gap in the job. |
| Ease of use | D | You install, configure and update the server yourself, in either edition. |
| Platforms and integrations | C | A web admin and standard protocols, with Sieve, LDAP and OpenID Connect. No apps of its own. |
An A is worth 4 points, a B 3, a C 2, a D 1 and an F nothing. The GPA is the average of the five.
Who Stalwart Mail Server is for
- Fits if you run mail for a company and want a modern single-binary server
- Works for admins who want multi-tenancy and are fine paying per mailbox
Who it is not for
- Skip it if you want a hosted service, as the cloud edition is listed for 2027
- Not for you if you have fewer than 25 mailboxes on Enterprise
- Skip it if you don't want to run and update a server
- Watch out: the monthly-billing rate isn't shown and prices switch between euros and dollars
Good to know
Good for
- Self-hosters who want one program instead of a separate MTA, spam filter and calendar server
- Hosting providers needing multi-tenant mail with per-tenant branding
- Organizations that want a per-mailbox license on their own infrastructure
Worth knowing
- Prices are shown in euros or dollars through a toggle; billing can be annual or monthly, and the monthly rate is not shown.
- Enterprise has a 25-mailbox minimum, and deployments above 100,000 mailboxes are quoted.
- Stalwart Enterprise Cloud, the hosted service, is listed as available in 2027, with interest registration only.
- You run and update the server yourself in either edition.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
$0.20
A month to start, paid by the year. There is a free plan too
Stalwart Mail Server has a free plan. Paid plans start at $2.40 per mailbox / year, billed annually (25-mailbox minimum).
Community
$0
Free AGPL-3.0 edition you host yourself, with the same protocols and core mail features as Enterprise.
Enterprise
$2.40
per mailbox / year, billed annually, 25 to 499 mailboxes
Adds multi-tenancy, branding, archiving and telemetry. Rate falls to $2.04 at 500 and $1.74 at 1,000 mailboxes.
The free plan
Community edition: the full mail server under AGPL-3.0, free to run on your own infrastructure.
Trying it first
30-day trial of the Enterprise edition with full access to Enterprise features.
Read from stalw.art on Nov 13, 2026.
Part 03 · Features
What it does
Its main features, where it runs, what it works with and who makes it
1
Place it runs: Web
Open-source mail and collaboration server written in Rust. Here is what it does, as its own site describes it, and what it covers: open source, self-hostable, calendar, email client, file sharing, dMARC.
Mail and collaboration in one server, with spam filtering, encryption at rest and clustering.
- Mail and collaboration in one server
- JMAP, IMAP and POP3 for mail, SMTP for delivery, plus calendars, contacts and file storage over CalDAV, CardDAV and WebDAV.
- Built-in spam and phishing filtering
- A statistical classifier, public blocklists, sender reputation and AI-driven analysis run inside the server.
- Sender authentication and transport security
- Handles DKIM, SPF, DMARC and ARC, plus DANE, MTA-STS and TLS reporting, with automatic certificate renewal over ACME.
- Encryption at rest
- Mailboxes can be encrypted with the user's own S/MIME certificate or OpenPGP key.
- Clustering
- Runs as a single node or as a cluster across regions.
- Enterprise multi-tenancy
- The Enterprise edition isolates tenants with their own accounts, domains, quotas and branding, for hosting many customers.
Where it runs
- Web
What it works with
- Sieve
- ACME
- LDAP
- OpenID Connect
Stalwart Mail Server is made by Stalwart Labs.
Part 04 · Standing
Where it stands
Its grades against its category, and whether to keep it or make your own
29/122
Other email apps it is graded above
Stalwart Mail Server's GPA of 2.2 is higher than 29 of the 122 other email apps we grade, and level with 24.
It stands best on features (B, above 79 of 122) and worst on ease of use (D, above 0).
Its paid plans start at $0.20 a month when paid by the year, against a middle price of $4.92 for the category: 0 of the 76 others that charge start lower.
On features, ease of use and platforms it scores 2.0 out of 4. 12 tools score higher and cost less.
Each grade against the category
Every bar is all 123 email apps we grade, cut by the letter each got. Stalwart Mail Server’s own letter is outlined.
- CValue for moneyAbove 13 of 122
- BFree plan and trialAbove 69 of 122
- BFeaturesAbove 79 of 122
- DEase of useAbove 0 of 122
- CPlatforms and integrationsAbove 10 of 122
Price against what you get
Each dot is one of 107 email apps. Further left costs less; higher up scores better on features, ease of use and platforms. Stalwart Mail Server is the marked dot.
What paid plans start at, a month (each step along is roughly double) →
Keep it, or make your own?
Whether this is something you could build for yourself with an AI app builder, and what you would give up.
Keep it
To replace Stalwart Mail Server you would be making an email client: sending, receiving, threading and searching years of mail. That is not a weekend's work, with an AI app builder or without one.
That makes this kind of software worth paying for, not this one in particular: 69 of the 122 other email apps grade higher. It costs $2.40 a year. Stalwart Mail Server is open source, so there is a third way: take its code and run it yourself.
What you could make
- Calendar: an app builder makes this well.
What you could not
- An email client: sending, receiving, threading and searching years of mail.
- Storing and serving files for other people.
- Reading the reports inbox providers send about your domain.
- Sharing with other people, which means accounts and invitations.
- The depth: we grade its features B, which means it covers the whole job.
What this rests on. Stalwart Mail Server’s listing: what it does, where it runs, what it plugs into and what it costs. It is a judgement about the kind of software this is. We have not built a replacement for it, and making your own means looking after it too. How we decide, and every tool’s verdict.
Part 05 · Alternatives
The alternatives
The tools it is most often weighed against, side by side
mailcow, Mailu, docker-mailserver, Modoboa and iRedMail
The 5 tools Stalwart Mail Server is most often weighed against, with where each one differs from it.
- 2.4GPA
mailcow
Free
Dockerized open-source mail server with a web admin UI.
- Stalwart Mail Server also covers file sharing and dMARC.
- 2.0GPA
Mailu
Free
Free Docker-based mail server with webmail and admin UI.
- Stalwart Mail Server also covers calendar and file sharing.
- 1.8GPA
docker-mailserver
Free
Self-hosted mail server packaged as a Docker container.
- Only Stalwart Mail Server lists a web app.
- Only docker-mailserver lists a Linux app.
- Stalwart Mail Server also covers calendar, email client, file sharing and dMARC.
- 2.2GPA
Modoboa
Free
Open-source mail server with a web admin panel and webmail.
- Stalwart Mail Server also covers file sharing and dMARC.
- 1.8GPA
iRedMail
Free plan · from $499/yr
Open-source mail server installer for Linux and BSD.
- Only Stalwart Mail Server lists a web app.
- Only iRedMail lists a Linux app.
- Stalwart Mail Server also covers file sharing and dMARC.
Part 06 · Questions
Quick answers
The questions people ask about it, each answered in a line or two
13
Questions, each answered in a line or two
The short version of everything above, for when you only need the answer. Each one is told in full in its part of the guide.
Is Stalwart Mail Server free?
Stalwart Mail Server has a free plan. Community edition: the full mail server under AGPL-3.0, free to run on your own infrastructure.
How much does Stalwart Mail Server cost?
Stalwart Mail Server lists 2 plans. Community: $0.
What platforms does Stalwart Mail Server work on?
Stalwart Mail Server is available on Web.
Does Stalwart Mail Server have an Android app?
No Android app was listed when its pages were read on Nov 13, 2026. Stalwart Mail Server is listed for Web.
Does Stalwart Mail Server have an iPhone app?
No iPhone app was listed when its pages were read on Nov 13, 2026. Stalwart Mail Server is listed for Web.
Is Stalwart Mail Server open source?
Yes. Stalwart Mail Server is open source, according to its own site.
What does Stalwart Mail Server integrate with?
Stalwart Mail Server's listing names Sieve, ACME, LDAP and OpenID Connect.
Does Stalwart Mail Server have a free trial?
Yes. 30-day trial of the Enterprise edition with full access to Enterprise features.
Who makes Stalwart Mail Server?
Stalwart Mail Server is made by Stalwart Labs.
What are the alternatives to Stalwart Mail Server?
The closest alternatives to Stalwart Mail Server in our directory are mailcow, Mailu, docker-mailserver, Modoboa and iRedMail.
How does Stalwart Mail Server compare with other email apps?
Stalwart Mail Server's GPA of 2.2 is higher than 29 of the 122 other email apps we grade, and level with 24.
Is Stalwart Mail Server good value for money?
ToolGPA grades Stalwart Mail Server C for value for money. Its paid plans start at $0.20 a month when paid by the year, against a middle price of $4.92 for the category: 0 of the 76 others that charge start lower.
Could I make my own version of Stalwart Mail Server?
To replace Stalwart Mail Server you would be making an email client: sending, receiving, threading and searching years of mail.
Where this guide comes from
The prices, plans, platforms and features were read from Stalwart Mail Server’s own pages on Nov 13, 2026, and the grades were given on Nov 13, 2026. Graded from this listing, whose facts were read from Stalwart Labs's own pages on 13 November 2026. Not based on using the product, and shorter than our full reviews.
Every tool we list gets five grades, A to F, each with its reason, and a GPA that averages them. How each is decided is at toolgpa.com/grades. This guide is ToolGPA’s own work; it is not made, paid for or approved by Stalwart Labs. Prices change, so check stalw.art before you buy.
Part 07 · About
About ToolGPA
Who made this guide, what else is on the site, and how to cite it
7,721
Tools graded, in 95 categories
ToolGPA grades software the way a school report grades a pupil: five subjects, a letter for each with the reason written beside it, and a GPA that averages them. Prices, plans and platforms are read from each maker’s own pages and dated, so you always know how fresh a figure is.
Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Every tool on the site has a guide like this one, free to download and pass on. It all lives at toolgpa.com.
7,721
tools graded
95
categories
739
price changes on record
579
apps priced in 12 countries
What else is on toolgpa.com
- Stalwart Mail Server, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/stalwart
- How grades are givenThe rules behind every letter and every GPAtoolgpa.com/grades
- Value chartsWhat each tool costs against what it scores, for every categorytoolgpa.com/charts
- CompareAny two tools side by side, plan by plantoolgpa.com/compare
- Price changesEvery price rise and cut on record, each with its sourcetoolgpa.com/price-changes
- Prices by countryWhat apps cost on the App Store in 12 countriestoolgpa.com/prices-by-country
- Pay lessEvery public discount: yearly billing, students, nonprofitstoolgpa.com/save
- Keep or makeWhich tools are worth paying for, and which you could build yourselftoolgpa.com/keep-or-make
Scan for the live page
Prices and grades as they are today
Quoting this guide?
Please name ToolGPA and link to the live page, so readers can check the figures for themselves:
ToolGPA, "Stalwart Mail Server: The Insider's Guide", checked Nov 13, 2026. https://toolgpa.com/tools/stalwart
Know someone choosing between email apps?
Send them this guide: toolgpa.com/tools/stalwart/guide
ToolGPA elsewhere: youtube.com/@toolgpa
See our other guides
The best-graded email apps after Stalwart Mail Server, each with an Insider's Guide of its own.
- Email Apps Insider's GuideEvery one of the 126 email apps we grade, compared
- Microsoft Outlook Insider's GuideMicrosoft's email and calendar app for desktop, mobile and web3.6 GPA
- AOL Mail Insider's GuideFree webmail with news and weather in a companion mobile app3.2 GPA
- BlueMail Insider's GuideCross-platform email client with a unified inbox and built-in AI3.2 GPA
Choosing software? Every tool graded, every price dated.
Compare tools at toolgpa.com ›Everything in this guide is ToolGPA’s own summary of what Stalwart Mail Server’s pages, its app-store listings and public reviews said on the dates shown. Grades are our judgement under the rules at toolgpa.com/grades. Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Stalwart Mail Server is a trademark of its owner, and this guide is not made, paid for or approved by Stalwart Labs. Prices and plans change: check stalw.art before you buy.