Issuer Identification Number

What is an Issuer Identification Number?

An Issuer Identification Number (IIN) is the first eight digits of the long account number found on the front of a plastic card that complies with the international standard ISO/IEC 7812. This sequence of numbers, which can be up to a maximum of 19 digits, is called the Primary Account Number (PAN).

The purpose of the IIN is to identify the card issuer and informs acquirers and card issuers how to route a transaction. The IIN is used by financial institutions and other companies.

Additional Information

In January 2017, ISO/IEC 7812 expanded from six digits to eight digits. Important information regarding the continued use of the IIN can be found here.

The Primary Account Number (PAN) is composed of an issuer identification number (8 digits), individual account identification (maximum 12 digits) and an accompanying check digit (1 digit), calculated by the Luhn formula (see ISO 7812:2017). The maximum 19 digits include  spaces used to separate the PAN for ease of visual reading as follows:

How to obtain an IIN

Pay.UK acts as an agent for the BSI (British Standards Institute) and is responsible for assigning UK National and International IINs on their behalf. We also sponsor IINs for overseas countries that don’t have their own sponsoring authority and manage this process on behalf of ISO/IEC JTC1/SC17.

Please download and fill out the relevant application form from the list below. Completed applications should be sent here.

UK National IIN

For institutions based in the UK ONLY.
Cost: £350 + VAT (one off payment).
To apply for a UK National IIN, please download and read the following application pack:

UK International IIN

For institutions based within the UK for cards designed for international acceptance.

Cost: £660 + VAT (UK card issuers are also charged an annual maintenance fee of £30 + VAT starting on the first anniversary of the assignment).

To apply for a UK International IIN, please download and read the following application pack:

Overseas International IIN

For institutions based outside the UK that do not have a Sponsoring Authority. Applications will be sponsored by Pay.UK Limited on behalf of ISO/IEC JTC1/SC17.

Cost: £660 (one off payment) (VAT zero rated for countries outside the EU).

To apply for an Overseas International IIN, please download and read the following application pack:

Register of UK Card IINs

To obtain a copy of the Register of UK Card IINs,(alpha and numerical), please download and read the following:


Completed applications should be sent here.