Pro plan (open source sponsorship program)
Free Pro tier for qualifying open source projects: 50,000 transactional emails per month via SMTP relay and HTTP API, unlimited verified domains, premium IP pool, inbound routing/webhooks, and delivery analytics; higher volume available on request.
Eligibility: for the project; OSI license required; non-commercial only; public repo required; Public repo on GitHub/GitLab/Codeberg or similar; maintainership verified via a project-linked email address; for the project itself, not commercial products.
How to apply: Submit repository URL, license type, sending use case and estimated monthly volume via the contact form on the offer page; review takes about two business days.
last verified 2026-07-07