Email Sending Services
Open-source email sending services
8 of the 51 email sending services in this directory are open source, according to their own sites.
All of them are free or have a free plan.
Listings checked up to Nov 13, 2026 · Where the facts come from
| Tool | Price | Free plan | Runs on |
|---|---|---|---|
| useSendOpen-source email sender built on Amazon SES | Free plan · from $10/mo | Yes | Web |
| Forward EmailOpen-source email forwarding and hosting for custom domains | Free plan · from $3/mo | Yes | Web, macOS, Windows, Linux, iOS, Android |
| PlunkOpen-source email platform for transactional and marketing mail | Free plan · from $0.001 | Yes | Web |
| Hyvor RelayOpen-source email API you can self-host | Free plan · from €10,000/yr | Yes | Web |
| NovuOpen-source notification infrastructure for apps and agents | Free plan · from $30/mo | Yes | Web |
| NodemailerFree Node.js library for sending email over SMTP and other transports | Free | Free | Web |
| FluentSMTPFree WordPress plugin for sending site email through your provider | Free | Free | Web |
| KumoMTAOpen-source mail server for high-volume, self-run email sending | Free plan · from $5,000/yr | Yes | Linux |
Common questions
Which email sending services are open source?
8 of the 51 email sending services in this directory are open source, according to their own sites. They are useSend, Forward Email, Plunk, Hyvor Relay, Novu, Nodemailer, FluentSMTP and KumoMTA.
When was this checked?
Each listing shows its own date. On this page they run from Nov 12, 2026 to Nov 13, 2026. Vendors change prices and plans without notice, so confirm on their site before you buy.
This page is built from the listings. A tool is here because its listing says so, and each listing names the pages it was read from.