---
title: "Customer"
description: "Saved payer details identified by the `customer_id` supplied by your integration. A customer can have saved payment instruments for subsequent payments."
image: "https://developer.sumup.com/og/index.png"
---

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Path: SumUp REST API

Saved payer details identified by the `customer_id` supplied by your integration. A customer can have saved payment instruments for subsequent payments.

## Fields

- `customer_id` (`Customer.customer_id`; string, required) — Identifier you supply when creating the customer. Use an ID from your own system and retain it for subsequent customer, checkout, and saved-payment-instrument requests.
  - example `"831ff8d4cd5958ab5670"`
- `personal_details` (`Customer.personal_details`; object, optional) — Personal details for the customer.
  - `first_name` (`Customer.personal_details.first_name`; string, optional) — First name of the customer.
    - example `"John"`
  - `last_name` (`Customer.personal_details.last_name`; string, optional) — Last name of the customer.
    - example `"Doe"`
  - `email` (`Customer.personal_details.email`; string, optional) — Email address of the customer.
    - example `"user@example.com"`
  - `phone` (`Customer.personal_details.phone`; string, optional) — Phone number of the customer.
    - example `"+491635559723"`
  - `birth_date` (`Customer.personal_details.birth_date`; string, optional) — Date of birth of the customer in `YYYY-MM-DD` format, without a time or timezone.
    - format `date`; example `"1993-12-31"`
  - `tax_id` (`Customer.personal_details.tax_id`; string, optional) — Identification number used for tax purposes, such as a CPF in Brazil.
    - maxLength 255; example `"423.378.593-47"`
  - `address` (`Customer.personal_details.address`; object, optional) — Profile's personal address information.
    - `city` (`Customer.personal_details.address.city`; string, optional) — City name from the address.
      - example `"Berlin"`
    - `country` (`Customer.personal_details.address.country`; string, optional) — Two letter country code formatted according to [ISO3166-1 alpha-2](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2).
      - example `"DE"`
    - `line_1` (`Customer.personal_details.address.line_1`; string, optional) — First line of the address with details of the street name and number.
      - example `"Sample street"`
    - `line_2` (`Customer.personal_details.address.line_2`; string, optional) — Second line of the address with details of the building, unit, apartment, and floor numbers.
      - example `"ap. 5"`
    - `postal_code` (`Customer.personal_details.address.postal_code`; string, optional) — Postal code from the address.
      - example `"10115"`
    - `state` (`Customer.personal_details.address.state`; string, optional) — State name or abbreviation from the address.
      - example `"Berlin"`


Source: https://developer.sumup.com/api/schemas/Customer/index.md