Mailgun Alternative (2026): Permanent Free Plan and Domain Mailboxes

Why people search for a Mailgun alternative

Mailgun has been a default for teams that outgrew "just SMTP": REST and SMTP side by side, routes that can parse and forward inbound mail, and ops tooling that scales with volume. People who already run production on Mailgun rarely search because "Mailgun cannot deliver."

"Mailgun alternative" in 2026 is usually one of these:

• The permanent free tier is gone—onboarding is a trial, then paid. Side projects, staging orgs, and agent prototypes lose a forever-small quota.
• Routing rules, sending domains, SMTP credentials, and REST endpoints overlap. You can make almost anything work; you can also spend a week deciding which path is "the" path for OTP mail.
• You want human mailboxes on the same domain (hello@, support@)—Mailgun is strong as a sending (and inbound-routing) platform, not a place for the team to live in webmail.
• Retries from workers and AI agents need an Idempotency-Key so a timeout does not mint a second code.
• You want one POST /emails plus signed delivery webhooks and inbound on the same organization, without modeling Mailgun's full routing graph first.

None of that says Mailgun is weak at complex inbound routing or high-volume ops. It says many searchers want a permanent free plan, domain mailboxes, and a simpler REST surface—while keeping transactional send. For the product matrix, see Rovela's Mailgun alternative page. This article is the engineering long-tail: free-tier removal, routing complexity, what the docs-backed Rovela path looks like, and how to migrate without inventing features.

Peers in other keyword classes (do not confuse the hooks): Resend alternative (mailboxes + inbound), SendGrid alternative (simple HTTP), Postmark alternative (permanent free + mailboxes), Amazon SES alternative (plain HTTP / no AWS). Here the primary keyword stays Mailgun.

When Mailgun is still the right tool

Stay—or dual-run—if:

• You depend on complex inbound routing (multi-route parse/forward/store graphs) that already match how your support or ticket pipeline works.
• You are an ops-heavy, high-volume shop where Mailgun's REST + SMTP + routes surface is a feature, not friction, and procurement cost of a switch dwarfs DX differences.
• Your stack already encodes Mailgun-specific routes, SMTP users, and event consumers you do not want to re-model this quarter.

Rovela targets teams that want Mailgun-class transactional sending, plus a permanent free tier, domain mailboxes, inbound, and Idempotency-Key behind a single POST /emails—without adopting Mailgun's full routing model first.

What "trial-only + routing-heavy" leaves open

Permanent free plan vs trial clock

Per Rovela's comparison, Mailgun's free on-ramp is framed as a trial period only—not a permanent monthly quota you can keep without converting. That is fine when you are already committed to paid volume. It is awkward for a forever-small SaaS, a demo org, or an AI agent prototype that should keep sending without a trial countdown.

Rovela's Free plan is permanent: 100 emails/month, 5 mailboxes, no card—full API, webhooks, and inbound included; upgrading raises limits rather than unlocking basics (Pricing, Mailgun alternative). Do not hard-code Pro or Enterprise numbers into architecture notes; re-read /pricing when you size volume.

Routing rules + REST + SMTP overlap

Mailgun can send over REST, speak SMTP, and express inbound behavior as routing rules. Power and overlap come together: teams often ask which credential, which domain object, and which route owns the OTP path. Rovela's comparison line is intentional—REST + SMTP, complex routing rules on one side; a single REST endpoint on the other (Mailgun alternative).

Rovela's send path is one call: POST https://api.rovela.dev/emails with Bearer auth and a flat JSON body. The API returns a queued message id. That is the whole happy path for transactional send (email API, Quick Start).

Send-focused product vs mailboxes humans can open

Mailgun optimizes programmable send (and inbound routing into apps). Rovela includes browser-accessible business mailboxes on your domain in the same org, so founders and support can reply from the same platform that sends OTP mail (webmail manual, SMTP). Free includes 5 mailboxes; paid plans raise counts and storage (Pricing).

Idempotency keys at the API layer

Rovela accepts an Idempotency-Key header (up to 256 characters); a retry within 24 hours returns the original response instead of sending again (email API, API: emails). That matters for queue workers and AI agents that retry on timeouts—without you inventing a dedupe table just to survive client retries against a large ESP surface.

Inbound and webhooks beside the send API

Inbound on Rovela is a first-class path: enable inbound on a verified domain, publish MX, subscribe to email.received, and fetch parsed content when your app needs it (Receiving email). Delivery events (email.delivered, email.bounced, email.complained, and more) push as signed webhooks (Webhooks overview). This is simpler than a Mailgun-style multi-route graph; it is also less expressive if you need that graph. Be honest about the trade: complex inbound routing shops may stay on Mailgun; teams that want "MX + webhook + fetch body" usually prefer the Rovela path.

Docs-backed map: send, auth, mailboxes, inbound

1. One send: POST /emails

Authenticate with a Bearer token from a key that has sending_access for production senders (Quick Start, Authentication). The from address must sit on a verified domain. There is no separate sandbox key that behaves differently from live (Quick Start).

curl -X POST https://api.rovela.dev/emails \
  -H "Authorization: Bearer re_your_sending_key" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: mailgun-migrate-otp-user_123-2026-11-05" \
  -d '{
    "from": "Acme <no-reply@yourdomain.com>",
    "to": "alice@example.com",
    "subject": "Your Acme code: 482913",
    "html": "<p>Your verification code is <b>482913</b>. It expires in 10 minutes.</p>",
    "text": "Your verification code is 482913. It expires in 10 minutes."
  }'

• Response shape: queued message id ({"object":"email","id":"..."}).
• Idempotency: same key within 24h → original response, no duplicate send.
• Overview: HTTP email API. No routing-rule object required for a basic OTP send.

2. Domain verification before the first real send

Add the domain in the dashboard, publish the DNS records shown (SPF, DKIM, DMARC, return-path), then verify (Quick Start, Domain guides). Sends from unverified domains are refused with a 400—not silently dropped. The Mailgun alternative FAQ notes most teams keep the same sending domain and usually adjust DKIM/SPF (and DMARC if missing).

3. Delivery webhooks

Register an endpoint with the events you handle; verify signatures; dedupe on event id (Webhooks, Security). Prefer webhooks over polling GET /emails/:id in production.

4. Business mailboxes, webmail, SMTP

• Webmail: rovela.email / webmail manual.
• SMTP for clients: host mx.rovela.dev, port 465 SSL/TLS; username = full address; password = per-device credential (SMTP). A mailbox sends only as itself, DKIM-signed with your domain key.
• Free includes 5 mailboxes; paid plans raise counts and storage (Pricing).

5. Inbound without modeling a route tree first

Enable inbound on a verified domain (full_access key), publish the returned MX, optionally list recipients when catch_all is false, subscribe to email.received (Receiving email). Deeper patterns: Inbound email API webhooks. If your product truly needs multi-step Mailgun-style routes, plan a deliberate redesign—or keep Mailgun for that slice and dual-run outbound OTP on Rovela.

Migration checklist (Mailgun-flavored)

1. Create a Rovela org and stay on Free while you prove the path (signup)—no trial clock on the free tier.
2. Verify the same sending domain you use today (DKIM / SPF / DMARC / return-path as shown).
3. Create a sending_access key for app servers; keep full_access for domain and inbound admin tooling.
4. Swap the client: one POST https://api.rovela.dev/emails with Bearer auth—map Mailgun's from/to/subject/html (or text) fields 1:1. Leave routing-rule migration for a second phase if you have one.
5. Add Idempotency-Key on OTP, magic-link, and receipt sends so retries do not double-fire.
6. Point webhooks at your existing bounce/complaint handlers; verify signatures before you cut traffic.
7. Optional: create mailboxes and enable inbound only after outbound OTP looks clean—especially if you are replacing a dense Mailgun route set.

Most teams report a first send quickly once DNS is under their control (Mailgun alternative page); mailbox and MX cutovers deserve a longer checklist, and complex route graphs deserve an explicit keep/replace decision.

Pricing without invented numbers

Need	Rovela Free (docs)	Notes
Monthly sends	100 emails	Per Pricing
Mailboxes	5	Same free plan
Card	Not required	Permanent free tier
API / webhooks / inbound	Included	Upgrades raise limits

Paid plans (Pro from the pricing page, Enterprise custom) increase email, domain, mailbox, and storage ceilings. Always re-read /pricing before you commit architecture to a number. Rovela's comparison restates Mailgun's free side as trial only—verify current Mailgun packaging on Mailgun's own site when you quote their pricing.

What this post is not

• Not a claim that Mailgun "fails" at delivery or inbound power—complex routing and high-volume ops are why many teams stay.
• Not a clone of /alternatives/mailgun; that page owns the feature matrix.
• Not a Resend, SendGrid, Postmark, or SES rewrite; those live at the sibling posts linked above. The hooks here are free-tier removal, routing complexity, and mailboxes.
• Not invented MCP tools, China-domestic ESP topics, or undocumented endpoints.

Next steps

1. Skim the Mailgun alternative matrix.
2. Send one message via Quick Start + POST /emails.
3. If humans need inboxes, add a mailbox and open webmail.
4. If replies or support@ matter—and you do not need a multi-route graph—enable inbound.
5. For passwordless flows, pair with OTP / magic-link spam and code vs link.

Bottom line: a Mailgun alternative search in 2026 often means you still respect Mailgun's routing and volume chops—but you want a free plan that does not expire, mailboxes your team can open, idempotent retries, and one POST /emails instead of a REST + SMTP + routes maze. Rovela is built for that stack. Verify every claim against the docs above, then migrate the OTP path first.