Open-source Mailchimp alternatives
Mailchimp bills per contact, forever, including contacts who unsubscribed. Self-hosting removes that entirely — a 200,000-name list costs the same as a 200-name one. What it adds is a server to run and deliverability to own.
Eleven projects below, with the licence, what each one asks of you, and the part the READMEs skip.
What each one asks of you
The difference between a weekend and a permanent responsibility is mostly in the third column.
| Provider | Licence and cost | What it asks of you | Type |
|---|---|---|---|
| Mautic | Open source | PHP, MySQL and reliable cron. Upgrades have a reputation. You bring the sending provider | Self-hosted |
| listmonk | AGPL-3.0 | One Go binary plus Postgres — the easiest here to run. No automation builder | Self-hosted |
| Keila | AGPL-3.0 | Elixir and Postgres, or a European hosted plan from €8/mo. No lifecycle automation | Self-hosted |
| Ghost | Open source (MIT) | Node and a database. Publishing and memberships rather than marketing automation | Self-hosted |
| Plunk | AGPL-3.0 | Postgres, Redis and a container, or $0.001 an email on Plunk Cloud | Self-hosted |
| useSend (formerly Unsend) | AGPL-3.0 | Postgres, Redis, your own AWS account — and it's still described as beta | Self-hosted |
| Notifuse | AGPL-3.0 | Postgres and a Go binary, plus a sending provider underneath. Cloud from $16/mo | Self-hosted |
| FluentCRM | $90/year, one site | Lives inside WordPress. Site down means marketing down; large sends strain WP cron | Self-hosted |
| Sendy | $69 one-time | PHP and MySQL on your own hosting, sending through your own Amazon SES account | Self-hosted |
| Mailcoach | Separate self-host licence | Hosted is $9.99/mo plus per-email; the self-hosted licence isn't published | Self-hosted |
| Postal | MIT | A full mail server — you own the IPs, the warm-up and the blocklist relationships | Self-hosted |
| Email Bump | Proprietary | Not open source and not self-hostable. The trade is that nobody pages you about a blocklist | Permanent |
From each project's own README, documentation and pricing page. Licences change; check before you build on one.
The licence is the easy part
Deliverability becomes yours. Mailchimp's price includes an abuse desk, warm shared IP pools and people who notice a Gmail deferral before you do. Self-hosting hands all of that back to you, and that transfer is worth more than the licence saving for most mid-sized lists.
Most of these don't send. listmonk, Mautic, Keila, FluentCRM and Sendy all hand off to Amazon SES or an SMTP provider you configure. So the licence is free and the sending isn't — budget roughly $0.16 per 1,000 emails on top.
Copyleft matters if you're building on it. Mautic, listmonk, Keila, Plunk, useSend and Notifuse are copyleft; Ghost, Postal and FreeResend are permissive. Running an unmodified copy for your own sending is fine either way.
What self-hosting actually saves against Mailchimp
Mailchimp's Standard plan is $20/mo at 500 contacts and scales from there, and it bills for unsubscribed contacts until you archive them. Take a 50,000-name list: on Mailchimp that's a meaningful monthly figure, and on listmonk plus Amazon SES it's roughly $8 of sending plus a small server.
That saving is real. Set against it: the server, the upgrades, the cron configuration, and the fact that when Gmail starts deferring your mail there is no support queue. At any realistic developer rate, a couple of incidents a year erases the difference for a mid-sized list.
The place self-hosting wins decisively is a very large list you email regularly, where the per-contact pricing of a hosted platform becomes the dominant cost. Below that, it's usually a preference about ownership rather than a saving.
Mailchimp alternatives, asked and answered
Is there an open-source Mailchimp alternative?
Several. Mautic is the closest on features — campaigns, segmentation, landing pages and lead scoring — running on PHP and MySQL. listmonk is the easiest to run: one Go binary and Postgres, with over 22,000 GitHub stars. Keila is AGPL with a European hosted option. Ghost covers publishing and memberships.
For WordPress sites, FluentCRM puts the whole thing inside your site for a flat $90/year with no per-contact charge.
Do open-source tools send the email themselves?
Mostly not. listmonk, Mautic, Keila, FluentCRM, Sendy and Notifuse all hand off to Amazon SES or an SMTP provider you configure, so the licence is free and the sending isn't.
Postal is the exception — it's a complete mail server, which means you own the IPs and the reputation as well as the software.
What does self-hosting cost in practice?
A small server, Amazon SES at $0.16 per 1,000 emails, and your own time. The time is the number people underestimate: installation, upgrades, cron configuration, monitoring and deliverability.
If nobody on the team wants to own an IP warm-up schedule, that's a signal rather than an obstacle to work around.
Or skip the on-call rotation
Contact-priced, with Amazon SES underneath and reputation management on top. Not open source — the trade is that nobody pages you about a blocklist. 5,000 contacts free.