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Head-to-head · SMTP Relay Services

Maileroo vs UniOne

  • Updated Oct 2026
  • Both researched from official sources
  • 3 checks side by side
Higher score Maileroo #5 in SMTP Relay Services 8.3/10 Free plan Free plan✓ 0 of 3 features Visit Maileroo
UniOne #8 in SMTP Relay Services 7.7/10 Paid ✓ 2 of 3 features Visit UniOne

Maileroo leads on 1 check, UniOne on 0, and 2 are even. Who comes out ahead on the 3 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest scoreMaileroo · 8.3/10
  • Free planonly Maileroo
  • Most featuresUniOne · 2 of 3

Maileroo scores higher on our rubric for smtp relay services: 8.3 against 7.7 out of 10; our editors rank them #5 and #8.

Maileroo offers free plan; UniOne doesn't.

Maileroo is the better fit for developers wanting broad transactional-email coverage. UniOne is the better fit for small senders wanting inexpensive API and SMTP access.

  • Maileroo fits best

    Developers wanting broad transactional-email coverage

  • UniOne fits best

    Small senders wanting inexpensive API and SMTP access

Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.

Side by side

Feature Maileroo 8.3/10 Visit ↗ UniOne 7.7/10 Visit ↗
At a glance
Editor score 8.3 7.7
Ranking #5 in SMTP Relay Services #8 in SMTP Relay Services
Best for Developers wanting broad transactional-email coverage Small senders wanting inexpensive API and SMTP access
Pricing model Free plan + paid Paid
Starting price — $6/mo
Free plan ✓ (best) —
Free trial — —
Deployment Cloud Cloud
Platforms Web Web
Support Email, Live chat, Docs Email, Live chat, Docs · 24/7
Compliance GDPR, 2FA, SSO/SAML GDPR, 2FA
Integrations 3 integrations 5 integrations
Built for Small business, Mid-market, Enterprise Small business, Mid-market, Enterprise
Features Maileroo 0/3 · UniOne 2/3
Inbound email parsing Not checked yet Not checked yet
Event webhooks Not checked yet ✓ (best)
Subaccounts Not checked yet ✓ (best)
Specs
Monthly send limit Not checked yet 6000 emails/mo
Dedicated IP option Not checked yet Dedicated
Email log retention Not checked yet 45 days
Our review
Pros
  • Free tier includes outbound and inbound email allowances
  • Supports SMTP, REST delivery, webhooks and inbound routing
  • Integrates with PHP, Laravel, Node.js, Python, Go, .NET and Java
  • SMTP API and REST/Web API support transactional and bulk email
  • Webhooks, tracking, templates, and validation support delivery operations
  • Separate projects, authentication, and dedicated IPs support account management
Cons
  • Free Plan is limited to 3,000 outbound emails monthly
  • Paid SMTP plan provides 25,000 emails per month
  • Dedicated IP options are aimed at higher-volume sending
  • The $0 trial is limited to four months and 6,000 monthly emails
  • The Standard plan is listed separately at $6 per month
  • Custom-volume features and priority support require the Individual plan
Our verdict

Maileroo is an email delivery platform for developers, startups, agencies and enterprises. It supports transactional, bulk and scheduled email through a RESTful API or SMTP relay, while inbound email routing connects incoming messages to…

Read the review →

UniOne is an API-powered email delivery service for transactional and bulk marketing communications. It supports SMTP and Web API sending, templates, visual email creation, event tracking, suppression management, domain authentication,…

Read the review →
  1. MailerooSMTP Relay Services 8.3Free plan
  2. UniOneSMTP Relay Services 7.7Paid

Strengths and trade-offs

  • Maileroo — where it wins

    • Free tier includes outbound and inbound email allowances
    • Supports SMTP, REST delivery, webhooks and inbound routing
    • Integrates with PHP, Laravel, Node.js, Python, Go, .NET and Java

    Where it doesn't

    • Free Plan is limited to 3,000 outbound emails monthly
    • Paid SMTP plan provides 25,000 emails per month
    • Dedicated IP options are aimed at higher-volume sending

  • UniOne — where it wins

    • SMTP API and REST/Web API support transactional and bulk email
    • Webhooks, tracking, templates, and validation support delivery operations
    • Separate projects, authentication, and dedicated IPs support account management

    Where it doesn't

    • The $0 trial is limited to four months and 6,000 monthly emails
    • The Standard plan is listed separately at $6 per month
    • Custom-volume features and priority support require the Individual plan
  • Maileroo8.3/10 · Free plan

    A developer-focused SMTP and API service with inbound routing, webhooks, templates and analytics.

    Visit MailerooFull verdict →
  • UniOne7.7/10 · Paid

    Affordable SMTP and API delivery with useful tracking, validation, and project controls.

    Visit UniOneFull verdict →

More comparisons

All SMTP relay services comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated · How we research and update