> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ionicfi.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Customers

> Buyer identity and reusable customer records.

Customers store buyer identity, contact details, addresses, metadata, and payment settings that can be reused across checkout and support workflows.

Use the generated endpoint pages for exact request and response payloads.

## Endpoints

| Endpoint                                                      | Use it for                                     |
| ------------------------------------------------------------- | ---------------------------------------------- |
| [Create customer](/api-reference/customers/create-a-customer) | Create a merchant-scoped customer.             |
| [List customers](/api-reference/customers/list-customers)     | Page through customer records.                 |
| [Get customer](/api-reference/customers/retrieve-a-customer)  | Retrieve one customer by `cus_` ID.            |
| [Update customer](/api-reference/customers/update-a-customer) | Change contact fields, addresses, or metadata. |

## Notes

* `email` and `creation_source` are required on create.
* `billing_address` and `shipping` are optional on create.
* On update, omitted address fields are left unchanged. Explicit `null` clears the nested value when supported by the handler.
* Customer list responses include summary data such as payment counts and spend by currency.