Dev tools · alternatives · 2026

24 alternatives to Kingmailer

Transactional SMTP Service

Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Kingmailer launched in 2017; newer entries below may have overtaken it.

1. 1
   MailerSend▲305

   Better transactional emails for teams.

   2020 · its alternatives →

2. 2
   Sender▲297

   Super easy and affordable email marketing platform

   2021 · sender.net · its alternatives →

3. 3
   Sidemail 2.0▲306

   Hi all! I'm Kristyna, maker of Sidemail. I'd love to share with you what we've been building. We built Sidemail because sending emails from a SaaS app was way harder than it should be. Sidemail is made for developers and teams that want one simple place to handle SaaS emails with reliable delivery and no bloat. It has: - Everything for creating, managing and delivering SaaS emails in one platform, - Easy-to-use email API for sending password resets, receipts, etc. - Messenger for writing product updates and newsletters, - Email automations for onboarding and lifecycle flows, - Fast email…

   Nov 2025 · sidemail.io · its alternatives →

4. 4
   MailerLogic▲96

   Email API with built-in deliverability intelligence

   Apr 2026 · mailerlogic.com · its alternatives →

5. 5
   Keplars▲116

   Email Infrastructure for Modern Product Teams

   Apr 2026 · keplars.com · its alternatives →

6. 6
   SMTPKit▲13

   Powerful SMTP & API for Transactional Emails

   2024 · smtpkit.com · its alternatives →

7. 7
   Mailazy▲203

   Cloud email infrastructure for the internet

   2022 · mailazy.com · its alternatives →

8. 8
   Mailercloud▲257

   Automate, optimize, convert, next level email automation

   2024 · mailercloud.com · its alternatives →

9. 9
   MailerSend - Transactional SMS API▲126

   Build strong customer connections with transactional SMS

   2022 · mailersend.com · its alternatives →

10. 10
    Maileroo▲118

    Transactional email delivery

    2023 · maileroo.com · its alternatives →

11. 11
    Mailerr▲119

    Automated Infrastructure for boosting Cold Email Delivery

    2025 · mailerr.co · its alternatives →

12. 12
    MailerLite▲290

    Intuitively-designed email marketing and website tools

    2014 · mailerlite.com · its alternatives →

13. 13
    Flowmailer▲63

    The email delivery platform you can rely on

    2020 · spotler.com · its alternatives →

14. 14
    Mailercloud Email API Platform▲165

    1,000+ Emails per Second with 99%+ Deliverability

    Mar 2026 · mailercloud.com · its alternatives →

15. 15
    BaseMailer▲12

    Give your emails superpowers.

    2020 · basemailer.com · its alternatives →

16. 16
    Minute Mailer▲221

    Mailchimp + Buffer in one simple platform.

    2015 · minutemailer.com · its alternatives →

17. 17
    Mailer▲7

    A lightweight development SMTP server

    2025 · iev.gumroad.com · its alternatives →

18. 18
    SelfMailKit▲13

    Send transactional & marketing emails

    2025 · its alternatives →

19. 19
    Sender SMS▲151

    Effortless and affordable SMS marketing platform

    2021 · sender.net · its alternatives →

20. 20
    AraMailer▲79

    Powerful email marketing software to get more sales & clicks

    2021 · its alternatives →

21. 21
    Mailercloud▲203

    Launch successful email campaigns like a pro

    2022 · mailercloud.com · its alternatives →

22. 22
    Gmail Transactional Email Relay by GMass▲79

    A free service to send transactional emails through Gmail

    2022 · gmass.co · its alternatives →

23. 23
    K2Mailer▲1

    Affordable bulk email marketing with reliable deliverability

    Aug 2026 · k2mailer.com · its alternatives →

24. 24MO
    Mailer – our in-house tool for sending email from the command line▲21

    2015 · dirwiz.com · its alternatives →

Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →