Courier Alternatives (January 2026)

API for Email, SMS, Web & Mobile Push Notifications | Courier

https://www.courie.com/

Courier is a notification API built for developers. Design once, and deliver to any channel – email, Slack, SMS, push, and more – all through a single API.

4.7/5

239+ reviews

Reviewed on:

Notification Infrastructure for email, sms, slack, push, inbox | SuprSend

https://www.suprsen

.com/

Meet SuprSend, a notification infrastructure to help developers build and manage notifications on all channels - sms, email, push, slack, chat and more - design once and send to all channels with a single API.

Engagespot | Notification infrastructure for developers

https://engagespo

.co/

Engagespot is a notification infrastructure that helps developers build delightful multi-channel communication experiences in their web and mobile apps.

Push Notification Software to Improve Customer Engagement - OneSignal

https://onesigna

.com/

The world’s leader for customer messaging including mobile push notifications, web push, SMS, email & in-app messaging. Trusted by 1 million+ developers.

SendPost Transactional Email API & SMTP Relay

https://app.sendpos

.io/

Email API and SMTP relay to not just send and measure email sending, but also alert and optimise. We provide you with tools, expertise and support needed to reliably deliver emails to your customers inboxes on time, every time.

Communication APIs for SMS, Voice, Email & Authentication | Twilio

https://www.twili

.com/

Connect with customers on their preferred channels—anywhere in the world. Quickly integrate powerful communication APIs to start building solutions for SMS and WhatsApp messaging, voice, and email.

Transactional Email API Service For Developers | Mailgun

https://www.mailgu

.com/

Powerful Transactional Email APIs that enable you to send, receive, and track emails, built with developers in mind. Learn more today!

Lightning fast email delivery powered by AI | SMTP & Email API

https://mailaz

.com/

Integrate in minutes and send transactional emails via our REST API or SMTP. Scale with our reliable global infrastructure and deliver emails to your customer's inbox instantly.

Test any email, SMS or user action with one API | Mailosaur

https://www.mailosau

.com/

Mailosaur removes the frustration of testing everything a user might do.  Test password resets, replies, two-factor logins, and more.

Email Delivery Service for Marketing & Developer Teams | Mailjet

https://www.mailje

.com/

Streamline your emailing and boost your sales with Mailjet. We serve all your email and SMS needs with one simple and powerful service.