Learn how to manage and retrieve customer information.


Our Customer API is responsible for the management and maintenance of any natural or legal person managed on the platform. This includes details of the person and their relationship to any product held on the platform.

The API enables you to create and manage customer profiles and search for customers based on their unique customerId or personal identifier. You can also use our API to verify a provided phone number and email address exists.

Customer Management

Retrieve Personal Identifying Information (PII) data about a customer using their customerId. If you do not have their customerId, you can search for the customer using one or more of the supported query filters.

customerIdUnique customer identifier.
givenNameThe given name (also known as the first name) associated with the customer profile.
familyNameThe family name (also known as the last name) associated with the customer profile.
postCodePostcode of the address associated with the customer profile.
phoneNumberThe phone number associated with the customer profile. (Phone number can be the home, work, fax, or mobile number).
dateOfBirthThe birthday and time associated with the customer profile, in  ISO 8601 format (i.e. "2000-07-19T09:14:44.568Z")

Customer Verification

Verify the customer’s email address and/or phone number exists through the Customer API. The API will verify that the email address and phone number exist but not confirm the possession. Confirm possession by sending a One-time Passcode (OTP).

We currently verify the mobile numbers registered to a network in the United Kingdom only. The endpoint assumes the country is the United Kingdom unless you prefix the mobile phone number with its international dialling code (e.g., +44 or 0044).

How does customer verification work?

The email address and phone number are validated similarly. Below is what a successful validation flow looks like.

  1. 1
    You initiate the call and provide the emailAddress or phoneNumber, depending on your chosen verification endpoint.
  2. 2
    The endpoint returns true or false to confirm the provided email address or phone number is verified.

Verification statuses

Both endpoints will return true or false depending on whether the email address or phone number is verified.

StatusValidation TypeDescription
truePhoneThe phone number is valid and the number is verified.
falsePhoneThe phone number is not valid because of a non-UK number format or the format is valid but not verified with network lookup or a valid number but it is not active on a network.
trueEmailThe mailbox exists and is reachable. Or we were unable to conclusively verify or invalidate the email address.
falseEmailThe mailbox is disabled, does not exist, is full or the syntax of the specified email address is incorrect. The email address could belong to a disposable email provider, seed, spam trap, black hole, technical role account or inactive domain.

Getting Started with NewDay

Quick start guides for how you can start working with NewDay as a partner and learn about the end to end processes of integrating with APIs.

Engagement with Commercial team

This section guides potential businesses on how to become a NewDay credit partner and explains the end-to-end on-boarding process.

Integration Guide for Developers

This section provides guidance on how to start building with NewDay i.e. how to integrate with NewDay's various deployment environments, getting access to APIs etc.

Still have questions?

Can’t find the answer to your question? Our friendly team are more than happy to help

Was this page helpful?