ActiveCampaign Postmark vs. Courier

Postmark is the email delivery service that people actually like. Stop worrying if your emails made it to the inbox, and get back to focusing on what matters—building great products. Start sending in minutes: With API libraries for pretty much every programming language you can think of, Postmark fits seamlessly into any stack. Stellar deliverability (without paying for a dedicated IP): You might say that Postmark has serious street cred with inbox providers.

Courier is notification infrastructure for customer messaging, built for humans and AI agents. It sits between your app and every channel you send on: email, SMS, push, in-app inbox, chat, and webhooks. You send one request, and Courier works out where it goes, what it looks like, and whether the user wanted it at all. Teams use it for the messages a product has to send: onboarding, alerts, receipts, reminders, and account notices. You keep the providers you already pay for. Courier is the layer above them.