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Home/Categories/Communication & Collaboration/Mailflare
Mailflare icon

Mailflare

Open source alternative to Fastmail, Google Workspace, Zoho Mail and Migadu

Host custom-domain email on your own Cloudflare account with Mailflare, a self-hosted inbox with full send/receive, smart rules, and zero mystery servers.

2.6K starsTypeScriptAGPL-3.0Active this week
Visit websiteGitHub repo
image of mailflare
Contents
  1. 01Who Mailflare is for
  2. 02The problem it solves
  3. 03How it solves it
  4. 04Strengths and trade-offs
  5. 05Mailflare vs alternatives
  6. 06Install and self-host
  7. 07Tech stack
  8. 08FAQ
  9. 09Similar open-source tools
TL;DR

Mailflare is a self-hosted email inbox for custom domains that deploys into your own Cloudflare account, replacing commercial services like Google Workspace and Fastmail with a private inbox you control. Unlike subscription-based providers, Mailflare stores mail in your own D1 database and attachments in your own R2 bucket, with no mystery servers or vendor tracking. Licensed under AGPL-3.0, the Community edition is free to self-host; the Team license ($249 perpetual) adds unlimited users and shared mailboxes. Best for developers and small teams who own custom domains, already use Cloudflare, and want professional email without a recurring per-seat subscription.AGPL-3.0 · TypeScript · 2.6K stars · Active this week

who it's for

Who Mailflare is for#

Freelancers managing email for multiple client domains

Mailflare supports multiple domains in a single deployment, so a freelancer or consultant can receive mail for every client domain from one workspace without a separate service per domain. Smart rules and labels keep client conversations organized within the same inbox.

Skip if:

You do not manage your clients' DNS through Cloudflare. Mailflare requires Cloudflare Email Routing, so domains must be on a Cloudflare-managed nameserver.

Small teams replacing Google Workspace for custom-domain email

The Team license ($249 perpetual) covers unlimited users and shared mailboxes. A small team migrating from Google Workspace avoids the $6+/user/month subscription and keeps mail data inside their own Cloudflare account rather than on Google's servers.

Skip if:

Your team relies on Google Calendar, Google Drive, or Google Meet tightly integrated with Gmail. Mailflare is an email inbox only and does not replace the broader Google Workspace suite.

Developers building apps that send transactional email

API keys let developers send transactional mail from their own applications through Mailflare's outbound infrastructure, using the same custom domain they receive on. Webhooks and audit logs provide visibility into what the app is sending.

Skip if:

Your app needs advanced transactional email features like template rendering, click tracking, or delivery analytics. Mailflare's API keys cover basic sending; purpose-built transactional providers offer more.

Privacy-focused individuals who want a self-hosted inbox

Mail data stays in D1 and attachments in R2, both inside the user's own Cloudflare account. There are no ad profiles and no mystery servers, per the project's own positioning. The Community edition is free to self-host for personal use.

Skip if:

You do not have a Cloudflare account and prefer to avoid any cloud vendor dependency entirely. Mailflare is not deployable on purely self-managed hardware.

the problem

The problem it solves#

Setting up professional email for a custom domain means choosing between expensive hosted services or complex mail server infrastructure. Google Workspace, Fastmail, Zoho Mail, and similar commercial providers charge per user per month, store your mail on their servers under their data policies, and give you no control over the underlying infrastructure. For freelancers and small teams, those per-seat costs add up fast, and switching providers means migrating years of mail across systems.

The alternative, self-hosting a traditional mail server, requires managing Postfix, Dovecot, spam filtering, and TLS certificates on a dedicated server. Most people who try it find the maintenance burden too high for a tool that should just work in the background. Mailflare takes a different approach: it runs on Cloudflare's infrastructure, which you already control if you use Cloudflare for DNS, and eliminates the server management problem entirely.

how Mailflare solves it

How it solves it#

Cloudflare-native deployment

Mailflare runs on Cloudflare Workers, D1, and R2, so there is no separate server to provision. Deploy with one click via the "Deploy to Cloudflare" button, then connect your domain and follow guided DNS checks for MX, SPF, and DKIM. The app name must stay "mailflare" for routing to work correctly.

Full inbox experience

Includes inbox, sent, drafts, spam, and trash folders alongside search, filters, attachments, autosaved drafts, and custom folders. New messages appear the moment they arrive via live updates. Attachments are stored securely in your own R2 bucket inside your Cloudflare account.

Smart routing rules

Create rules to route, label, forward, or archive incoming messages automatically. Rules fire on delivery, so incoming mail is sorted before it reaches your inbox. You can also block unwanted senders and set up automatic replies.

Multi-account and shared mailboxes

Supports separate personal, team, and client accounts with delegated access controls. Shared mailboxes give multiple team members access to the same inbox, with role-based permissions. Shared mailbox access requires the Team license ($249 perpetual).

API keys for transactional mail

Generate API keys from the dashboard to send transactional email from your own apps using the same Mailflare sending infrastructure. Webhooks and audit logs provide visibility into outbound activity. Outbound sending requires a Cloudflare Paid Workers plan ($5/month).

Manual and scheduled backups

Export mailbox data manually or on a schedule for portable copies you can store anywhere. Backups cover the D1 database, making them straightforward to restore without vendor-specific tooling.

strengths · trade-offs

Strengths and trade-offs#

Strengths

  • Data stays in your Cloudflare accountMail data lives in D1 and attachments in R2 inside your own Cloudflare account. Unlike hosted email providers, no third-party reads or stores your mail. You retain full control over the database and can export it at any time.
  • No recurring per-seat cost for the base tierThe Community edition is AGPL-3.0 licensed and free to self-host for personal use. Your Cloudflare usage typically fits within free allowances for small personal installations. The only cost to add sending is the Cloudflare Paid Workers plan ($5/month), which covers the whole account, not per user.
  • One-click deployment with no server managementCloudflare Workers handle all compute; there is no VPS, no Docker Compose stack, and no operating system to patch. Deployment runs through the Cloudflare dashboard in minutes, making this one of the simplest email self-hosting paths available.
  • Active development with a growing communityThe repo has 2,551 stars and 274 forks and was last pushed on September 3, 2026, indicating active maintenance. Open issues stand at 6, suggesting a well-managed backlog. Named sponsors are listed on the project website, signaling external investment in the project's future.

Trade-offs

  • -Cloudflare account required, no alternative deploymentMailflare runs exclusively on Cloudflare infrastructure (Workers, D1, R2, Email Routing). There is no Docker image, no bare-metal path, and no self-hosted option outside of Cloudflare. Teams that do not already use Cloudflare or prefer to avoid a single cloud vendor have no alternative deployment path.
  • -Outbound sending requires a paid Cloudflare planReceiving email is free, but sending requires a Cloudflare Paid Workers plan at $5/month. This is an account-level cost, not per user, but it is an additional dependency that users must budget for if they want a full send/receive inbox.
  • -Shared mailboxes locked to the Team licenseShared mailbox access and unlimited users require the Team license, priced at $249 at launch (normally $399). This is a perpetual license, not a subscription, but it is a meaningful upfront cost for teams that need multi-user shared access.
  • -AGPL-3.0 restricts reselling as a managed serviceThe Community edition is AGPL-3.0, which means you can run it for yourself and your team, including internal commercial use, without restriction. What is not permitted is offering Mailflare as a managed hosted email service to third parties without distributing your source changes.
versus alternatives

Mailflare vs alternatives#

Mailflare vs Google Workspace

Google Workspace is the dominant commercial email provider for custom domains, at $6/user/month (Business Starter) or higher. Mailflare is an alternative for teams that want custom-domain email without a per-seat recurring subscription.

FeatureMailflareGoogle Workspace
LicenseAGPL-3.0Proprietary
Self-hostingYes (Cloudflare account)No
PricingFree (Community) / $249 Team perpetual$6+/user/month
Data locationYour Cloudflare D1/R2Google's servers
SendingCloudflare outbound ($5/mo add-on)Included

Mailflare is the better choice when data ownership matters: your mail stays in your own Cloudflare account, not on Google's infrastructure. For a small team with 5 seats, Mailflare's $249 Team perpetual license costs less over two years than Google Workspace at $360/year. The real trade-off is the ecosystem: Google Workspace includes Calendar, Drive, Meet, and Docs tightly integrated with Gmail. Mailflare covers email only, so teams that depend on the full Google Workspace suite will need to supplement it with separate tools.

Mailflare vs Fastmail

Fastmail positions itself as a privacy-focused commercial alternative to Gmail, starting at $3/user/month. Like Mailflare, it supports custom domains and is built for professionals. Unlike Mailflare, Fastmail is a hosted service: your mail lives on Fastmail's servers, not in infrastructure you control.

FeatureMailflareFastmail
LicenseAGPL-3.0Proprietary
Self-hostingYes (Cloudflare account)No
PricingFree (Community) / $249 Team perpetual$3+/user/month
Data locationYour Cloudflare D1/R2Fastmail's servers
Mobile appsWeb interfaceNative iOS/Android apps

Mailflare wins on data ownership and long-term cost for teams. Fastmail wins on polish: it has mature native mobile apps, established spam filtering, and a reputation built over two decades. Mailflare's web interface is production-ready but younger; users who prioritize a native mobile experience or battle-tested spam filtering should weigh Fastmail as a serious option.

Mailflare vs Migadu

Migadu is a small commercial provider that serves power users who want custom-domain email with minimal overhead, typically at a flat monthly rate rather than per-seat pricing. Both Migadu and Mailflare target technically savvy users who want professional custom-domain email without big-vendor infrastructure.

Mailflare's key advantage over Migadu is that your data never leaves your own account: it sits in Cloudflare D1 and R2, which you control. Migadu stores your mail on their servers under their retention policies. Mailflare also costs less for teams once the perpetual Team license is paid for. Migadu's advantage is simplicity: it works on any domain with standard DNS, with no Cloudflare dependency, and has a refined interface built over years of production use.

install · self-host

Install and self-host#

bash
Deploy to your Cloudflare account with one click, or run a local development server with the following setup steps.
```bash
cp .dev.vars.example .dev.vars
npm install
npm run db:migrate:local
npm run dev
```
tech stack · detected from GitHub

What it's built on#

Languages
TypeScript
Frameworks
Next.jsReact
frequently asked

FAQ#

Is Mailflare free to use?

The Community edition is AGPL-3.0 licensed and free to self-host. Receiving email costs nothing beyond your existing Cloudflare plan; sending email requires a Cloudflare Paid Workers plan ($5/month account-wide). Pro and Team licenses are available as one-time perpetual purchases for users who need custom branding or multi-user shared mailboxes.

Does Mailflare require a Cloudflare account?

Yes. Mailflare runs on Cloudflare Workers, D1, and R2, and uses Cloudflare Email Routing for inbound delivery. You must have a Cloudflare account and manage your domain's DNS through Cloudflare to connect it to Mailflare. There is no deployment option outside of Cloudflare.

Can Mailflare send and receive email?

Yes. Inbound delivery uses Cloudflare Email Routing. Outbound sending works from the inbox UI and through API keys for apps. A Cloudflare Paid Workers plan ($5/month) is required for outbound sending; receiving email works on the free Cloudflare plan.

Where is my email data stored?

Mailbox data lives in Cloudflare D1 (a SQLite-backed database) inside your Cloudflare account. Attachments are stored in Cloudflare R2. Neither Mailflare nor a third-party service holds your mail; it stays inside the infrastructure account you control. Manual and scheduled backups let you export portable copies of the database.

What does the AGPL-3.0 license allow?

You can run Mailflare for personal use, internal team use, and internal commercial team use without restriction. What AGPL-3.0 does not allow is offering a modified version of Mailflare as a hosted managed email service to others without distributing your source changes. Running it for your own team is fully permitted.

also worth a look

Similar open-source tools#

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Repository

Stars
2.6K
Forks
275
License
AGPL-3.0
Last commit
today
Last verified
Sep 3, 2026
Repo
hieunc229/mailflare ↗

Additional details

Language
TypeScript
Open issues
6
Contributors
9
First release
2026

Categories

Communication & CollaborationCloud & HostingIT Management

Tags

Self HostedEmailCloud NativeDeveloper Tools