Skip to main content
DuoCircle vs.

DuoCircle 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 → See what we make

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)
  • 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 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 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 (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 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→See what we make