What is an ABN in Australia? A plain-English guide

An ABN — Australian Business Number — is the unique 11-digit identifier that every registered business in Australia must have. It is issued by the Australian Tax Office and turns up everywhere business is done: on invoices, job ads, payslips and company websites. If you have come across the term while job hunting and were not sure what it meant, this guide explains it in plain English.

An ABN is public information. Anyone can look up any ABN for free, which means you do not need special access or permission to check the business behind a job ad. Looking up an employer's ABN before you apply or share personal details is a simple step that takes under ten seconds, and it puts real government data in front of you instead of guesswork.

An ABN lookup on the Australian Business Register shows you a handful of useful facts: whether the ABN is active or cancelled, the legal name the ABN is registered to, the entity type (company, sole trader, trust or partnership), whether the business is registered for GST, and how long the ABN has been active. None of it requires an account.

GST (Goods and Services Tax) is a 10% tax on most goods and services in Australia. Businesses with an annual turnover over $75,000 are required to register for it. Sole traders and newer businesses below that threshold may not be registered for GST, and that on its own is not a concern — it often just means the business is small or new. The Australian Tax Office sets and collects GST.

ASIC (the Australian Securities and Investments Commission) maintains the national register of company and business names. A company registered with ASIC will have an ACN (Australian Company Number) in addition to its ABN. Sole traders and partnerships do not have ACNs. You can look up company details directly on ASIC Connect.

In short: an ABN is for any business entity, while an ACN is specifically for companies registered under the Corporations Act. A company will have both an ABN and an ACN. A sole trader will only ever have an ABN.

Every Australian employer must have an ABN. If an employer cannot or will not provide one when you ask, that is worth noting before you share personal documents or accept a role. You can read how to verify an employer ABN for the practical steps, and the frequently asked questions cover the most common situations.