What is IRD Number (New Zealand)?

Every person and entity that has obligations to IRD in New Zealand needs an IRD number. For individuals, the IRD number is issued automatically when they first engage with the tax system (applying for a job, opening a bank account, registering a company). For companies, an IRD number is required at incorporation and is obtained through myIR or the IR596 paper application.

**Format** IRD numbers are either 8 digits (old format, still in use) or 9 digits (the current standard). They are typically displayed with hyphens: 12-345-678 or 123-456-789. The last digit is a check digit calculated from the others. An IRD number cannot be transferred, cancelled or reused. If an individual has multiple IRD numbers (which sometimes occurs through administrative error), they must contact IRD to have them consolidated.

**Company vs Individual IRD Numbers** A company has its own IRD number, separate from the IRD numbers of its directors and shareholders. Directors do not use their personal IRD number for company tax obligations. Each entity (the company, each individual director) maintains their own IRD account.

**New Zealand Business Number (NZBN)** The NZBN is a 13-digit number assigned by the Companies Office to all New Zealand companies and, since 2018, to other types of business entities including sole traders, partnerships and incorporated societies. The NZBN is a public identifier used on commercial documents (invoices, contracts) and in B2B data sharing. It is separate from the IRD number and does not replace it.

**Where the IRD Number is Required** IRD number is required for: filing income tax returns, registering for GST or as an employer, applying for KiwiSaver enrolment, opening a New Zealand bank account for a business, completing certain conveyancing transactions (land sales over NZD 1 million), and providing to investment income payers (banks, fund managers) to avoid 45% non-declaration withholding.

**Withholding Without an IRD Number** If an individual does not provide their IRD number to their employer or to a bank paying interest, income tax is withheld at the no-declaration rate of 45% (employees) or the non-declaration rate (investment income). Providing the IRD number ensures the correct rate applies.

**Application Process** Individuals can apply online via myIR, at an AA Driver Licensing Agent, or by completing an IR595 form with supporting identity documents. Companies registered on the New Zealand Companies Register automatically receive an IRD number if they select that option during online incorporation. Processing takes 8 to 10 working days for manual applications.