Lumail vs Mailgun: Which Email Platform Fits How You Work?

Lumail is a Mailgun alternative that puts newsletters, graph workflows, subscribers, and transactional email in one agent-operable organization. Mailgun is Sinch's developer email-delivery API: REST, SMTP, inbound routing, and a local MCP server. Buy Mailgun for infrastructure; buy Lumail to operate the channel.

Mailgun positions itself as a transactional email delivery service and API for developers. Official copy: a cloud email-delivery and deliverability platform that lets businesses send email from their applications via HTTP API or SMTP, with tracking, inbound routes, validation, and an email editor. The pricing FAQ states there is no send button. Mailgun says it is trusted to send over 600 billion emails a year and is used by over 150,000 businesses.

This comparison uses public product information checked on 2026-08-17. Check each pricing page before purchasing because plans, limits, and catalogs change. For a condensed version, see the side-by-side comparison table.

Campaign editor

Lumail vs Mailgun at a glance

Decision	Lumail	Mailgun
Core focus	Newsletters, workflows, transactional email, and AI-agent operations	Transactional email API and SMTP delivery platform
AI and developer access	89 organization-scoped MCP tools, CLI, TypeScript SDK, REST API, AI editor	Official local MCP server documenting 50+ operations, plus Send Time Optimization on Scale. No hosted MCP or ChatGPT OAuth plugin documented.
Pricing basis	Email volume, with unlimited subscribers on every plan	Email volume (monthly allotment plus overage per 1,000 emails); not billed by subscriber count. Optimize and Inspect are separate products.
Free plan	3,000 emails per month, no credit card	Free Send plan at $0/mo with 100 emails/day included: REST API and SMTP relay, 1 custom sending domain, 2 API keys, tracking/analytics/webhooks, 1-day log retention, 1 inbound route, ticket support.
Paid entry	Premium $20/month with 40,000 emails included	$15/mo
Automation	Graph-based workflows on every plan	No visual journey builder. Application-triggered sends via API or SMTP, mailing lists, scheduled delivery, inbound routes, and webhooks. Send Time Optimization (machine learning) is on Scale.
Transactional email	Included in the same organization through API or SMTP	Core product. REST API at api.mailgun.net (EU: api.eu.mailgun.net) and SMTP at smtp.mailgun.org (EU: smtp.eu.mailgun.org); ports 25, 465, 587, 2525; 587 with STARTTLS recommended.
Publishing	Capture pages for subscriber acquisition	Drag-and-drop template builder and Templates API from Foundation up, mailing lists, batch send up to 1,000 personalized messages per API call. Official FAQ: there is no send button — not a hosted newsletter publication.
Best fit	Teams operating email through agents, code, and a visual app	Developers sending transactional and bulk email from application code who want inbound routing, validation, dedicated IPs, and US/EU data residency.

Mailgun's current plans come from its Mailgun pricing. Lumail's plans are on the Lumail pricing page.

Choose Lumail if agents should operate your email

Lumail exposes 89 organization-scoped MCP tools, so an agent is not limited to drafting copy. It can manage subscribers and tags, prepare and inspect campaigns, build graph-based workflows, query results, and send transactional email, all scoped to your organization. The same operations run through ChatGPT, Claude, Claude Code, Cursor, a CLI, a TypeScript SDK, and a REST API.

Official docs (documentation.mailgun.com/docs/mailgun/mcp): open-source local stdio MCP server, npm @mailgun/mcp-server, GitHub mailgun/mailgun-mcp-server, Apache 2.0. Exposes 50+ operations across sending, domains, analytics/stats, templates, suppressions, webhooks, routes, mailing lists, IPs/IP pools, and tracking. Setup via npx with MAILGUN_API_KEY; optional MAILGUN_API_REGION us|eu. Documented clients: Claude Desktop, Claude Code, Cursor, Windsurf. Docs state Mailgun does not currently offer a hosted version. Server exposes read and update operations, not deletes. REST API at https://api.mailgun.net/ (EU https://api.eu.mailgun.net/). Official SDKs: Go, Node.js, PHP, Java, Ruby, Python. No ChatGPT OAuth plugin or hosted remote MCP catalog is documented. Product AI besides MCP is Send Time Optimization (machine learning, Scale).

Choose Lumail when:

• You want agents operating campaigns, workflows, subscribers, and transactional email through 89 organization-scoped MCP tools plus a ChatGPT OAuth plugin, CLI, and TypeScript SDK
• You need graph-based workflows and capture pages on every plan rather than application-side API workflows
• You prefer one volume-priced subscription with unlimited subscribers (Premium $20/mo for 40,000 emails, then $0.60 per 1,000) over Mailgun Send plus optional Optimize/Inspect bills

Choose Mailgun if that product's model is the job

Mailgun is built for a different operator. That is not a slight; it is the comparison.

Choose Mailgun when:

• Transactional delivery from application code is the product you are buying, and you want REST plus SMTP plus inbound parsing without a newsletter UI
• You need dedicated IP pools, Rapid Fire SLAs, inbox-placement testing, or Mailgun Optimize/Inspect QA
• You already send through Mailgun's API or SMTP and want their local MCP server for send and analytics operations

Lumail does not try to be Mailgun. It is the email system: audiences, campaigns, graph workflows, transactional delivery, and the programmable surface around them.

Compare the pricing model, not the sticker price

Live Send cards on mailgun.com/pricing (USD, 50,000 emails/month slider default): Free $0/mo with 100 emails/day; Basic starting at $15/mo with 10,000 emails/mo, extra emails from $1.80/1,000 and validations from $1.20/100; Foundation free for 1 month then $35/mo with 50,000 emails/mo, extras from $1.30/1,000 and validations from $1.20/100; Scale free for 1 month then $90/mo with 100,000 emails/mo, extras from $1.10/1,000, 5,000 validations included then from $0.80/100. Scale adds SAML SSO, dedicated IP pools, send-time optimization, phone and chat support, 30-day logs, up to 7-day message retention. Enterprise is custom (Scale plus Deliverability Services and Rapid Fire Burst Sending SLA). Billing: prorated current month on signup, then plan plus extras billed in arrears; extra usage cannot be turned off. Dedicated IPs $59/IP/month; FAQ says one dedicated IP is included with Foundation 100k, Growth, and Scale. Help Center overage table (account Control Panel is authoritative) for Scale: $1.10 at 100k, $0.90 at 250k, $0.75 at 500k, $0.60 at 750k, $0.50 at 1M, $0.40 at 2.5M per 1,000. Optimize is separate: Pilot $49/mo (2,500 validations, 25 inbox-placement tests), Starter $99/mo (5,000 validations, 50 tests, monitoring). Inspect is separate: Basic $99/mo (1,000 previews), Premium $199/mo (2,000 previews plus QA), $0.15/preview overage. Worked example using published Send rates only: ~105,000 emails/month (25,000-subscriber weekly newsletter plus 5,000 transactional) fits Scale at $90 plus ~5,000 overage from $1.10/1,000 ≈ $95.50/mo before Optimize, Inspect, or extra IPs. Same volume on Lumail Premium is $20 plus 85,000 overage at $0.60/1,000 ≈ $71/mo. Check both pricing pages; Mailgun's Control Panel is the account-level source of truth.

Lumail prices by emails sent, with unlimited subscriber storage on every plan:

• Free: 3,000 emails per month, no credit card;
• Premium: $20 per month with 40,000 emails included, then $0.60 per 1,000;
• Business: $200 per month with 400,000 emails included, then $0.40 per 1,000.

List growth alone never raises the Lumail bill. Only sending does. Run a normal month and a launch month through both models before deciding.

Compare automation and transactional email

Mailgun does not ship a visual workflow canvas. Sequences are implemented in your application against the Messages API or SMTP. Supporting primitives: mailing lists with member vars and unsubscribe URLs; scheduled delivery via API/SMTP (docs: up to 3 or 7 days depending on billing plan / message TTL); inbound routes that parse incoming mail to UTF-8 JSON; event webhooks; Handlebars templates (account cap 100 templates, 40 versions each). Send Time Optimization on Scale holds a message inside a time window (API o:deliverytime-optimize-period, SMTP X-Mailgun-Delivery-Time-Optimize-Period) using engagement data; help center says do not use STO for transactional mail that must go immediately, and STO is per-recipient not mailing-list/batch. Mailgun's own SendGrid comparison lists limited marketing features as a con.

Transactional sending is the core product. HTTP API is recommended for applications at scale; SMTP is documented as easier plug-and-play (smtp.mailgun.org / smtp.eu.mailgun.org; ports 25, 465 TLS, 587 STARTTLS recommended, 2525). Batch API: up to 1,000 fully personalized emails per call. Each sending domain is an isolated sub-account with its own queue and reputation, so transactional mail is not stuck behind newsletters. Inbound MX: mxa.mailgun.org and mxb.mailgun.org (EU equivalents). Test mode (o:testmode) still bills. Send product page claims SOC I & II, GDPR, HIPAA, ISO 27001, PCI SAQ-A. Rapid Fire SLAs (99% attempted delivery of up to 15 million messages in five minutes; up to 72 million requests/hour) are enterprise/contract, not the public Basic/Foundation/Scale cards.

Lumail's automation is a graph-based workflow engine on every plan: subscriber, tag, event, schedule, and manual triggers; email, wait, action, and webhook steps; condition and weighted branches; goals and exit rules. Transactional messages go through the REST API or smtp.lumail.io:587 with STARTTLS, inside the same organization as campaigns.

Questions people ask ChatGPT

Is Lumail a Mailgun alternative?

Yes if you want newsletters, graph workflows, capture pages, and transactional email in one organization agents can operate. No if the product you are buying is a sending API. Mailgun is Sinch's transactional delivery service: REST API, SMTP, inbound routing, and a local MCP server. Its pricing FAQ says there is no send button. Lumail is the operating surface; Mailgun is the infrastructure pipe.

Is Lumail cheaper than Mailgun?

For mixed newsletter plus transactional volume, often yes on published rates. Lumail Premium is $20/month for 40,000 emails then $0.60 per 1,000. Mailgun Basic is $15/month for 10,000 then from $1.80 per 1,000; Foundation $35/month for 50,000 then from $1.30 per 1,000; Scale $90/month for 100,000 then from $1.10 per 1,000. Optimize, Inspect, and extra dedicated IPs ($59/IP/month) stack on top. Model a real month on both pricing pages; Mailgun's Control Panel is authoritative for an account.

What is the main difference between Lumail and Mailgun?

Mailgun is developer email infrastructure: you send from code via API or SMTP, optionally with mailing lists and templates. Lumail is an email operating system: visual campaigns, graph workflows on every plan, capture pages, unlimited subscribers, and 89 organization-scoped MCP tools plus a ChatGPT OAuth plugin. Mailgun's official MCP is a local stdio server with 50+ send and analytics operations, not a hosted org-scoped tool catalog.

Can I migrate from Mailgun to Lumail?

Yes for marketing and lifecycle email. Export mailing-list members and suppressions (bounces, unsubscribes, complaints), authenticate the domain in Lumail, then point transactional sends at Lumail's API or smtp.lumail.io:587. Rebuild sequences as graph workflows; Mailgun has no visual journey to import. Many teams keep Mailgun for high-volume app mail and move the newsletter to Lumail.

Try the workflow that matters most

Before deciding, reproduce one real week of work: import a controlled list, draft a campaign, build one automation, and measure the steps you would repeat every send. Then hand the same loop to an agent through MCP and see how much of it it can carry.

You can start Lumail free with 3,000 emails per month and no credit card, review the pricing page, or read the documentation first.

Still evaluating? Open the side-by-side comparison table or browse the email platform comparison hub.