MailHog
Mail ServersEmail testing tool with a fake SMTP server
Replaces Mailtrap
The 56 best Lightweight mail servers you can self-host, ranked by community traction.
Email testing tool with a fake SMTP server
Replaces Mailtrap
Email and SMTP testing tool with web UI
Replaces Mailtrap, MailHog
Privacy-focused, searchable email client
Replaces Gmail
Modern command-line email client written in Rust
Replaces Mutt, Outlook
Catch-all SMTP server for inspecting test email
Replaces Mailtrap
Composable, all-in-one mail server in Go
Replaces Google Workspace, Microsoft 365
Modern, secure all-in-one mail server
Replaces Google Workspace, Microsoft 365
High-performance, pluggable SMTP server in Node.js
Replaces SendGrid, Mailgun
Simple, modern and fast web-based email client
Replaces Gmail, Outlook Web
Synchronization and migration tool between IMAP accounts
Replaces IMAP migration services
Fake SMTP server for development email testing
Replaces Mailtrap
Feature-rich terminal email client
Replaces Microsoft Outlook
Efficient terminal-based email client
Replaces Gmail, Outlook
Fast, modern spam filtering system
Script to deploy a full Postfix/Dovecot mail server
Replaces Google Workspace
Browser extension for OpenPGP encryption in webmail
Replaces ProtonMail
Lightweight webmail aggregator for many accounts
Replaces Gmail, Outlook Web
Lightweight, fast and modern webmail client
Replaces Gmail, Outlook Web
Swiss Army knife for SMTP testing
Replaces Mailtrap
Parser and dashboard for DMARC aggregate reports
Replaces Dmarcian, Valimail
Web interface for managing Postfix mail domains
Replaces cPanel Email
Secure, high-performance IMAP and POP3 server
Replaces Microsoft Exchange
Simple, easy-to-configure SMTP server
Replaces Google Workspace
Console-based threaded email client
Replaces Mutt
Scriptable IMAP mail filtering utility
Replaces Gmail filters
Fast, tag-based email indexing and search system
Replaces Gmail search
Graphical editor for Sieve mail filtering scripts
Replaces Gmail filters
Terminal email client with a modern interface
Replaces Mutt, NeoMutt
Flexible and widely deployed mail transfer agent
Replaces Microsoft Exchange
Terminal-based mail user agent for notmuch
Replaces Mutt
Simple and extensible web-based email client
Replaces Gmail
Sync Gmail with a local notmuch mail database
Replaces Gmail web interface
Synchronize IMAP mailboxes to local Maildir
Replaces Outlook offline mode
Tool for one-time IMAP mailbox migration
Replaces Hosted migration services
Secure and simple SMTP server from OpenBSD
Replaces Sendmail, Postfix
Fast, secure and reliable mail transfer agent
Replaces Microsoft Exchange
Web interface for managing virtual mail domains
Replaces cPanel email
Minimal, instant-onboarding mail server for Delta Chat
Replaces WhatsApp
IMAP and Maildir mailbox synchronizer
Replaces Outlook offline mode
Free webmail front-end for IMAP and SMTP servers
Replaces Gmail, Outlook Web
Initial tagging script for the notmuch mailer
Replaces Gmail filters
Rule-based and Bayesian anti-spam mail filter
Replaces Proprietary spam filtering appliances
Lightweight SMTP client for sending mail
Replaces Sendmail
Fetch and filter mail with a single configuration
Replaces fetchmail, procmail
Tiny mail transfer agent for outbound delivery
Replaces Sendmail, Postfix
Lightweight and fast GTK email client
Replaces Microsoft Outlook
Remote mail retrieval and forwarding utility
Replaces Gmail import
Simple relay-only mail transfer agent
Replaces Sendmail
Flexible mail retrieval tool for POP3 and IMAP
Replaces fetchmail
DMARC policy enforcement filter for mail servers
Replaces Proprietary DMARC services
DKIM signing and verification filter for mail servers
Replaces Proprietary email security gateways
Encrypting mailing list manager with OpenPGP
Replaces Google Groups
Fast Bayesian spam filter for mail systems
Replaces Proprietary spam gateways
Sieve mail filtering engine for Dovecot
Replaces Gmail filters
DKIM signing and verification milter for mail servers
Replaces Hosted email authentication
Small POP3 client for retrieving mail
Replaces fetchmail
No apps match these filters.
Every option here is open-source and self-hostable, tagged Lightweight within the mail servers category. Compare them on the individual app pages for setup difficulty and resource requirements.