Courier

Courier is a customer messaging orchestration platform for software teams. Its documentation says it "helps you send and manage your product's notifications across email, SMS, push, Slack, Microsoft Teams, WhatsApp, and in-app, all in one place." It handles transactional notifications (password resets, receipts, alerts) and lifecycle sequences (onboarding, re-engagement, announcements) on the same platform, and it is built for developers first, with product and growth teams working alongside them in visual tools. One thing sets it apart from an ordinary email service, and it shapes everything else: Courier does not deliver the mail itself. You connect your own sending providers and Courier sits on top of them.

How sending works

The docs answer the question directly: "You bring your own providers. Courier sits on top of the delivery services you already use, so you keep your sender reputation, domains, and provider pricing." For email that means accounts such as SendGrid, Postmark or Amazon SES; for SMS, Twilio; for push, Firebase Cloud Messaging and APNs. The home page says you can switch providers "without rewrites or vendor lock-in", and the docs add that it can fail over to a backup provider if one is unavailable. Courier supplies the routing, failover, templating, user preferences and analytics, and bills for those per send, separately from what your providers charge.

Multi-Channel Routing sends each message across email, SMS, push, Slack or Microsoft Teams, and in-app "based on user preferences and your rules."

What a sender gets

Design Studio. A visual template editor lets anyone design templates, test changes and ship updates "in minutes across every channel you use." The docs call it "Design once, send anywhere": one template is formatted for email, SMS, push, chat and the inbox, and wording or design changes go out without a code deploy. A Drop-In Designer can be embedded in your own product so your customers edit their own message templates.

Journeys. Journeys are "visual, multi-step workflows that automate when and how messages send", with triggers, delays, branches and send steps. Batch and digest nodes bundle activity into a single notification, and the docs mention experiments. Journeys can be built in the dashboard or through the Journeys API, and the docs include a guide to building a three-email welcome series. The home page pitches it to non-technical teams, who "build and iterate while Courier handles timing, routing, and delivery logic." Broadcasts send one message to a whole list or audience, built from static lists and dynamic audiences.

AI agents in journeys. The home page says Courier runs "GPT-5.4, Claude Opus, and other frontier models as a step in any workflow," to score users, generate personalized content, enrich profiles and return structured output. On the pricing page the AI Agent node and AI Translations come with the Business plan.

Preferences and the inbox. Users choose which notifications they receive, per topic and per channel, and Courier checks those choices on every send; you can host a ready-made preference center or embed preference components. Courier Inbox adds a real-time notification center and toasts to web, iOS, Android, React Native and Flutter apps. The Inbox page says it syncs read state across email, push and in-app "so users never see the same message twice," updates over WebSockets, shows each user only their own messages, and can be live "in under an hour." Twilio, Vanta and Photoroom are named as Inbox users.

Multi-tenant apps. Tenants scope branding, preferences and routing per customer or workspace, so one integration can serve many end customers, each with their own look and delivery rules.

Logs and analytics. Every send gets a log entry with status, timeline, content and the provider's response. Delivery, open and click rates are tracked per template, journey and broadcast, and outbound webhooks push each status change into your own systems.

Developer tooling. Courier is API-first. Server SDKs cover Node, Python, Go, Ruby, Java, PHP and C#; client SDKs cover React, JavaScript, iOS, Android, React Native and Flutter. There is a CLI, an MCP server and Courier Skills so AI coding tools such as Claude Code, Cursor and Codex can build notification workflows.

Plans and pricing

The pricing page is short: "Start free with 10,000 sends a month, then pay $0.005 per send as you grow. No per-seat or no channel add-ons fees."

• Developer, free: 10,000 sends per month, journeys and broadcasts, the MCP server, CLI and SDKs, SSO via Google or GitHub, and email support. Log retention is 7 days.
• Business, $0.005 per send: pay-as-you-go with unlimited notifications, plus AI Translations, the AI Agent node, cross-device email testing and email and chat support. Log retention is 30 days.
• Enterprise, custom: volume pricing, a dedicated Slack channel, observability integrations, role-based access control, an enterprise SLA and EU Data Residency. Log retention is 1 year.

The comparison table also lists digest and batching, custom environments, multi-tenant support, internationalization, custom link tracking URLs and data warehouse integrations across the platform, and custom SSO, a support SLA, an uptime SLA and MSA, DPA, BAA and legal review at the top tier.

Security and compliance

The docs say "Courier maintains SOC 2, HIPAA, and PCI DSS programs, and supports GDPR and CCPA obligations," with current reports, including the SOC 2 report and the latest penetration test, in a Security Portal. Courier is "a managed cloud platform, with no self-hosted or on-premise option", and for data residency the EU option "keeps notification data in Europe."

Customers

The customers page names Twilio, CircleCI, LaunchDarkly, Nav, Trusted Health, Fluint, Side, Bluecrew and Workleap. Nav uses Courier for banking and credit product notifications tied to real-time product events. Trusted Health, a healthcare staffing marketplace, moved its product notifications off marketing tools onto Courier: SMS carries time-sensitive clinician alerts, email carries summaries and daily job-match digests, and hospital managers get in-app notifications in its Works platform.

Who it suits

Courier fits a software company whose notifications come from product events and whose engineers want them out of the codebase: SaaS apps, marketplaces, fintech and healthcare products, developer platforms. The free tier covers a young product, and per-send pricing stays predictable. It is not a newsletter or campaign tool for a marketing team working alone, and it needs an email provider account behind it, since Courier routes the mail rather than delivering it.