Flowmails vs Mailgun
Developer-oriented transactional email (Sinch). This page is a side-by-side on the parts that matter when you're considering a switch — data residency, pricing, and the parts of each stack that show up in a real migration.
At a glance
Three sentence compare.
Pricing shape
Mailgun's free tier is 100 emails/day for 1 month; paid plans start at $15 / month for 10,000 emails. Flowmails' Base plan is $0; Pro is $9.9 / month and Enterprise is $39.9 / month.
Setup shape
Mailgun is hosted — sign up, verify domain, call the API. Flowmails connects your domain provider over OAuth and runs the shared mail worker for every tenant.
Best fit
Mailgun: teams that need its deliverability tooling (inbox placement, validation) and its email-list / routes products. Flowmails: teams that want inbound mail and route tables without the breadth.
Feature matrix
Mailgun vs Flowmails, line by line.
| Feature | Mailgun | Flowmails |
|---|---|---|
| Data residency | Mailgun multi-tenant (Sinch) | Flowmails' own storage, scoped by domain id |
| Inbound routing | Yes (Routes product) | Yes (route tables, scoped by domain id) |
| SMTP relay | Yes | No |
| Email validation | Yes (paid add-on) | Not bundled |
| Mailing lists | Yes | No (transactional only) |
| Per-email pricing | Yes (volume tiers) | No |
Integration parity
SDK and runtime compatibility.
Mailgun exposes both an HTTP API and an SMTP relay. Flowmails is REST-only. SDK-wise, the surface areas are similar (send / receive / stats).
Migrating
How to switch from Mailgun to Flowmails.
Decide whether you need Mailgun's optimisation / validation products
If your team depends on Mailgun's inbox placement reports or email validation, plan for those independently — Flowmails doesn't bundle equivalents. If you only ever used Mailgun for send / receive, the migration is straightforward.
Connect the domain's provider
Same prerequisite as every other Flowmails flow: the zone must be on a supported routing provider — Cloudflare is the one we support today, with the provider SPI open to others.
Replace the SDK
Swap Mailgun SDK calls for Flowmails SDK calls. Templates are plain HTML, so the renderer is unchanged. If you used Mailgun's inbound routes, port them into Flowmails' route tables (an allow-list of exact local parts, not regex).
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