Courier vs Knock (2026): which should you pick?

Pick Courier if

• Fits if you send mail, SMS and push from one product and want one API
• Works for small apps that stay under 10,000 sends a month

Look elsewhere if

• Skip it if you want Courier to deliver email itself, since it routes through your own provider
• Tight if you pass 10,000 sends a month, when Business charges $0.005 per send
• Pricey if you send high volume, where 100,000 sends works out at $500
• Watch out: AI Translations, the AI node and EU data residency are on Business
• Watch out: Device Preview is an extra from $20 a month

Pick Knock if

• Fits if you're a product team and want one workflow to reach email, in-app and chat
• Works for apps that already have an email provider and need preferences and batching on top

Look elsewhere if

• Skip it if you want a service that sends email by itself: it needs a provider you connect
• Pricey if you outgrow free, because the next step is $250 a month
• Tight if you want the Knock branding gone, as that needs Starter or higher
• Watch out: email client previews, SAML SSO, SCIM and translations sit on dearer plans, and the HIPAA BAA is Enterprise only

Courier

• The Business plan has no monthly fee and charges $0.005 per send, with AI Translations, the AI node and EU data residency.
• The Developer plan stops at 10,000 sends a month.
• The Device Preview add-on is from $20 a month.
• Courier routes through your own email provider rather than delivering the mail itself.

Knock

• Knock is an orchestration layer, so email delivery goes through a provider you connect; it is not a standalone sending service.
• The jump from Free to Starter is $250 a month, with messages beyond 50,000 billed at $0.005 each.
• Removing Knock branding, email client previews and priority email support need Starter or higher.
• Custom roles, SAML SSO, SCIM, translations and the HIPAA BAA are listed on Enterprise only.

Courier

Omnichannel routing

One send can go to email, SMS, push, chat or in-app, with fallback between providers.

Journeys

Multi-step messaging triggered and personalized from your data.

Design Studio

A no-code visual editor with multi-channel preview.

In-app Inbox

An embeddable notification center that syncs across devices.

AI agent step

Run a language model as a step in a workflow to score users or generate content.

Provider connections

Bring your own email, SMS, push and chat providers.

Knock

Cross-channel workflows

A workflow is a single type of message, such as a user invite, that can branch, delay and route across email, in-app, push, SMS and chat.

Broadcasts and in-app guides

Broadcasts send a one-time message to an audience on any channel. In-app guides cover banners, modals, cards and tooltips rendered with your own components.

Batching and preferences

Batch and digest notifications to cut frequency, and let recipients manage preferences by channel, notification and category.

Email through your own provider

The integrations list names email providers including SendGrid, Postmark, Amazon SES, Mailjet, Mailgun, Mailtrap and MailerSend.

Agent and MCP access

Workflows, templates, guides, broadcasts and audiences can be managed from Claude, ChatGPT, Cursor and Slack, through a remote MCP server or the Knock CLI.

Multi-tenancy

Built-in multi-tenancy is listed on every plan, and per-customer branding and preferences on Enterprise.

Courier

• Developer$0

  10,000 sends a month, journeys and broadcasts, MCP server, CLI and SDKs, SSO via Google and GitHub, email and chat support.

• EnterpriseCustom

  Everything in Business plus volume pricing, a dedicated Slack channel, observability integrations, role-based access control and an enterprise SLA.

Knock

• Free$0

  Up to 10,000 messages sent, 500 guide recipients and 500 agent credits each month. No credit card required.

• Starter$250

  per month, plus additional usage

  Includes 50,000 messages (then $0.005 each), 2,500 guide recipients and 2,000 agent credits. Removes Knock branding; adds email client previews.

• EnterpriseCustom

  Annual agreements with volume-based pricing, custom roles, SAML SSO, SCIM, enterprise SLAs, HIPAA BAA and priority support over Slack, email and calls.