# Customer.io ESP Suppression API

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

Customer.io ESP Suppression 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 ESP Suppression. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.

If you use Customer.io as your email service provider (ESP), these endpoints help you retrieve information about email addresses suppressed directly by the ESP. ESP-based suppressions are different from suppression in Customer.io: these are addresses that the ESP suppressed automatically because a message bounced, a customer requested they not be contacted again, etc. These are _not_ addresses that you deleted and suppressed either in our UI or through [the API](#operation/suppress).

## Machine-readable artifacts (3)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/customer-io/refs/heads/main/openapi/customer-io-esp-suppression-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

ESP Suppression

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