Open Source Email Marketing
In email marketing the list is the only asset that matters, and hosted senders meter it - pricing climbs with every contact, and a flagged campaign can get your account suspended with the audience still inside it. Deliverability rides on sender reputation you never fully control. The open source options here keep the subscriber list and the sending logic on your own infrastructure, so the relationship with your readers stays yours.
listmonk
Self-hosted newsletter, mailing list, and transactional email manager with a single-binary app and PostgreSQL
BillionMail
Self-hosted open-source mail server and email marketing platform with analytics and customer management
Mautic
Open source marketing automation with self-hosting, lead management, and privacy-focused campaign control
Mailtrain
Self-hosted newsletter app with subscriber lists, segmentation, MJML templates, automation, and reports
Dittofeed
Open-source customer engagement for broadcasts and automated journeys across email, SMS, push, WhatsApp, and Slack
SendPortal
Self-hosted email marketing and newsletter software with subscriber lists, campaigns, tracking, and reports
Keila
Open source email newsletter tool for campaigns, sign-up forms, and self-hosted sending
phpList
Open source email marketing manager for newsletters, campaigns, analytics, and subscriber segmentation