--- title: "DuoCircle Outbound SMTP vs. Mailgun | DuoCircle" description: "How DuoCircle Outbound SMTP compares to Mailgun for transactional and application email sending. Free tier of 1,000 emails per month, no credit card required, with engineering-led support and the same delivery infrastructure DuoCircle has run since 2014." image: "https://www.duocircle.com/images/og-default.png" canonical: "https://www.duocircle.com/resources/mailgun-alternatives/" --- DuoCircle vs. # Outbound SMTP vs. Mailgun How DuoCircle Outbound SMTP compares to Mailgun for transactional and application email sending. Free tier of 1,000 emails per month, no credit card required, with engineering-led support and the same delivery infrastructure DuoCircle has run since 2014\. [ Talk to an Expert → ](/contact/) [ Visit Outbound SMTP ](https://outboundsmtp.com) Coverage match \~85% on SMTP Price ratio \~50% Capability Outbound SMTP DuoCircle Mailgun category leader SMTP relay HTTP API Reputation + throttling DKIM signing Inbound parsing routes Email validation API Free tier (100/day, included) Operating since 2014 Outbound SMTP pricing 1,000/mo free + per-volume Pricing on the website. No quote-only gating. Mailgun pricing 100/day free + per-volume Verify against their current public posture. Capability comparison ## Outbound SMTP vs. Mailgun, by capability Honest table. Where the leader covers more, we say so. Capability Outbound SMTP DuoCircle Mailgun category leader SMTP relay HTTP API Reputation + throttling DKIM signing Inbound parsing routes Email validation API Free tier (100/day, included) Operating since 2014 Pricing on the website ## DuoCircle Outbound SMTP vs. Mailgun Mailgun (now part of Sinch) is one of the established names in transactional and developer-focused email sending. They offer SMTP relay plus an HTTP API, deliverability tooling, and a broad set of integrations. DuoCircle Outbound SMTP covers the SMTP relay job at roughly half the cost, with a 1,000-email-per-month free tier and the same direct engineering relationship across the rest of our portfolio. ### What DuoCircle Outbound SMTP covers - **SMTP relay for application mail** (transactional, system notifications, password resets, receipts) - **Free tier**: 1,000 emails per month, no credit card required to start - **Volume-based pricing** beyond the free tier - **Reputation, throttling, and routing** handled inside the platform - **Sub-account / multi-tenant support** for platforms sending on behalf of customers - **Detailed delivery logs and APIs** for integration into your own dashboards ### What Mailgun covers that DuoCircle doesn’t - **HTTP-first API** as a primary product (DuoCircle Outbound SMTP is SMTP-relay-led; for an HTTP-first API see our [Developer Email API](/email/developer-email-api/)) - **Deliverability and reputation tooling at full Mailgun scope**, including more elaborate inbox-placement reporting - **The Sinch communications-platform integration**, including SMS and other channels in the same vendor relationship - **Larger SDK matrix** across more programming languages and frameworks ### Pricing comparison - **Mailgun pricing** has a free trial and then scales by volume; the standard tiers run roughly twice DuoCircle’s pricing for equivalent monthly send volume. - **DuoCircle Outbound SMTP pricing** starts at 1,000 emails per month free, with no credit card required, and scales by volume on the published rate card. → **[Visit outboundsmtp.com](https://outboundsmtp.com/?utm%5Fsource=duocircle&utm%5Fmedium=capability&utm%5Fcampaign=cross%5Fsell)** for current pricing and free signup. ### When to choose Mailgun - You need an HTTP-first API as the primary sending mechanism (or use our [Developer Email API](/email/developer-email-api/) at unsent.dev as the DuoCircle alternative for that shape) - You want a multi-channel communications platform (email + SMS + voice) under one vendor - Their broader SDK matrix or specific integration is a hard requirement ### When to choose DuoCircle Outbound SMTP - You want SMTP relay specifically (no app rewrite, no proprietary SDK) - You’re starting small and want a real free tier (1,000/month) without a credit card - You appreciate engineering-led support and the rest of the DuoCircle portfolio under one engineering team - The 90/50 ratio (about half the cost for the same capability) is meaningful at your volume ### When to look elsewhere from both - **If you need cold-outreach campaigns** with multi-step sequences, see [Cold Email Outreach](/email/cold-email-outreach/) (NuReply) instead. Cold outreach belongs on the sender’s own mailboxes, not on a shared relay. - **If you need a marketing-campaign platform** with templates, segmentation, and visual editors, that’s a different category from SMTP relay. [Talk to an Expert](/contact/) about your sending pattern. ## Ready to talk? Same-day response from someone technical. We tell you yes or no quickly. If yes, we get to work. [Talk to an Expert→](/contact/)[See what we make](/products/) ```json {"@context":"https://schema.org","@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. 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