# Customer.io Transactional API

**Canonical:** https://apis.io/apis/customer-io/customer-io-transactional-api/  
**Provider:** Customer.io — https://apis.io/providers/customer-io/  
**Base URL:** https://api.customer.io  
**Documentation:** https://docs.customer.io/integrations/api/track/

Customer.io Transactional API is one of 42 APIs that [Customer.io](https://apis.io/providers/customer-io/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. Tagged areas include Transactional. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.

Send transactional messages such as password resets, purchase receipts, and other important notifications triggered by user actions.

## Machine-readable artifacts (3)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/customer-io/refs/heads/main/openapi/customer-io-transactional-api-openapi.yml
- **Documentation** — https://docs.customer.io/integrations/api/app/
- **Documentation** — https://docs.customer.io/integrations/data-in/connections/http-api/

## Other Customer.io APIs (12)

- [Customer.io Track API](https://apis.io/apis/customer-io/track-api/)
- [Customer.io Activities API](https://apis.io/apis/customer-io/customer-io-activities-api/)
- [Customer.io Alias API](https://apis.io/apis/customer-io/customer-io-alias-api/)
- [Customer.io Batch API](https://apis.io/apis/customer-io/customer-io-batch-api/)
- [Customer.io Broadcasts API](https://apis.io/apis/customer-io/customer-io-broadcasts-api/)
- [Customer.io Campaigns API](https://apis.io/apis/customer-io/customer-io-campaigns-api/)
- [Customer.io Collections API](https://apis.io/apis/customer-io/customer-io-collections-api/)
- [Customer.io Customers API](https://apis.io/apis/customer-io/customer-io-customers-api/)
- [Customer.io Exports API](https://apis.io/apis/customer-io/customer-io-exports-api/)
- [Customer.io Group API](https://apis.io/apis/customer-io/customer-io-group-api/)
- [Customer.io Identify API](https://apis.io/apis/customer-io/customer-io-identify-api/)
- [Customer.io Messages API](https://apis.io/apis/customer-io/customer-io-messages-api/)

## Tags

Transactional

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/customer-io/customer-io-transactional-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/customer-io/.