Two different regimes, not one relabelled
The United Kingdom asks a company for its number, its registered office and the part of the UK it sits in. Australia asks for something else entirely: an ACN from ASIC, an ABN from the Australian Business Register, and, once a business trades under anything other than its own exact identity, a registered business name on top of both. Reading the UK rules and assuming the Australian ones are the same list with different labels is the mistake this tool exists to stop.
The ACN and the ABN are not interchangeable, except when they genuinely are
Corporations Act 2001 section 153 puts a company's name, and either its ACN or a matching ABN, on invoices, letters, receipts, statements, orders, letterhead, official notices, and on any cheque, promissory note or letter of credit issued in the company's name. The substitution only works where the last nine digits of the ABN match the ACN, in the same order, per section 153(2). That is the common pattern, an ABN built from two extra digits in front of the ACN, but it has to be checked rather than assumed: an ABN that does not line up cannot stand in, and the ACN itself still has to be shown.
A sole trader or partnership never has an ACN
ASIC issues an ACN to a company on registration, and only to a company. A sole trader and a partnership are identified by an ABN, never an ACN, however carefully somebody has read the company rules first. This tool keeps the two identifiers separate on purpose, because the more likely mistake is not getting a number wrong, it is going looking for a number that was never going to exist.
The business name exemption is exact, and Australia forgives less than the UK
Under the UK's rules a partnership can add "and Company" or "& Co" without creating a business name at all. ASIC's own Regulatory Guide 235 draws the Australian line stricter: the exemption covers an individual trading under their own name, a partnership trading under all the partners' names, or a company trading under its own registered name, and nothing else. The guide's own worked example is "John Smith & Co": even that small an addition means the name needs registering. Once registered, the business name and the ABN, if there is one, have to appear on the business documents connected with it, and at any premises open to the public.
A trading name does not replace a company's own duty
A company trading under something other than its own registered name is not swapping one duty for another. Its own name and ACN, or a matching ABN, still have to appear under section 153, and the registered business name plus the ABN appear as well wherever the trading name is used, under section 19. Both sets of particulars sit on the same document rather than one replacing the other.
Websites, and the registered office, run the other way from the UK
Two differences cut against what a UK-familiar reader would expect. Nothing found for this tool puts a website on either statutory list here, where the UK's own regulations name a company's website directly. And where every UK company must show its name at its registered office, section 144 only extends that particular duty to a public company: a proprietary company, which is what most small Australian businesses are, has no equivalent duty there, though every company still has to display its name at any place it carries on business open to the public.
What a breach actually costs
Trading under an unregistered business name is an offence under section 18, with a maximum of 30 penalty units on prosecution, currently $10,920 at the Commonwealth penalty unit value of $364 for conduct on or after 1 July 2026. The ongoing duties to show a registered name correctly, on documents and at premises, are separate offences under sections 19 and 20, each up to 5 penalty units. These are maximums a court could impose, not an automatic fine: ASIC's own stated approach is to write to a business first, reminding it of its obligations. Nothing found for this tool ties a disclosure breach to a business's ability to sue on a debt, unlike the UK's own rules in narrow circumstances. The Australian consequence is regulatory rather than a defence for whoever owes the money.
Wording, not certification
Everything this asks for is already public by law. An ACN, a company name and a registered office are on the ASIC register precisely so that anybody can look them up, which is the whole point of a disclosure duty, so there is no privacy claim worth making about a page that arranges them into a footer.
What is worth saying is the other half. This builds the wording the legislation asks for. Whether a particular document satisfies it in your situation is not something a free tool can certify, and that judgement stays with you or with whoever you ask to check it.
Common questions
Where does my ACN actually have to appear?
On your invoices, letters, receipts, statements of account, orders for goods and services, business letterhead and official notices, always alongside your full company name. It also has to appear on any cheque, promissory note or letter of credit issued in the company's name. Corporations Act 2001 (Cth) s153 is the source, and unlike the UK, an Australian invoice needs the number as well as the name: there is no shorter list that lets an invoice carry only the name. Your name also has to be displayed at any place the company carries on business that is open to the public, under s144. None of it is required on packaging, envelopes, business cards, vehicles or a machine-generated receipt.
Can I show my ABN instead of my ACN?
Only where the last nine digits of the ABN are the same, and in the same order, as the ACN. That is usually true, because the common pattern is an ABN built from two extra digits in front of the ACN, but it is not guaranteed, so the digits need checking rather than assuming. Where they line up, s153(2) lets you print “Australian Business Number” with the ABN instead of “Australian Company Number” with the ACN. Where they do not, the ACN itself still has to appear.
I am a sole trader. Do I need an ACN?
No, and you cannot get one even if you wanted to. ASIC issues an ACN only to a company registered under the Corporations Act. A sole trader, and a partnership, are identified by an ABN instead, never an ACN. If you came to this looking for your ACN after reading about company rules, this is the point where those rules stop applying to you at all.
I trade under a name that is not my own. What do I actually have to do?
Register it as a business name with ASIC, if it is not registered already, then show the business name and your ABN, if you have one, on the business documents connected with trading under it, and at any premises open to the public. The exemption for trading under your own identity is exact. ASIC's own regulatory guide gives the example “John Smith & Co” and states plainly that even that small an addition means the name needs registering. There is no Australian equivalent of the UK's tolerance for a partnership adding “and Company” or “& Co” for free.
Does my website need any of this?
Not as a legal requirement. Neither the Corporations Act's ACN duty nor the Business Names Registration Act's disclosure duties name a website, which is a genuine difference from the UK, where a company's website sits on the statutory list. Showing the same particulars there anyway is sensible practice: a customer who cannot work out who they are dealing with is the one who disputes the invoice later.
What happens if I do not register my business name?
Trading under an unregistered business name is an offence under s18 of the Business Names Registration Act, carrying a maximum of 30 penalty units on prosecution, currently $10,920 at the Commonwealth penalty unit value of $364 for conduct on or after 1 July 2026. That is a maximum a court could impose, not an automatic fine: ASIC's own stated approach is to write to a business first, reminding it of its obligations, before taking anything further. Once registered, not showing the name correctly on documents or at premises open to the public are separate offences under s19 and s20, each up to 5 penalty units.
My company also trades under a shop name. Do I need both sets of details?
Yes. Registering a business name does not replace your company's own disclosure duty. That is the part that catches people out. Your company's full name and its ACN, or a matching ABN, still have to appear under s153, and your registered business name plus your ABN have to appear as well wherever the trading name is used, under s19. The two regimes sit on the same document rather than one replacing the other.
Is this the same as the UK trading disclosure rules?
No. The UK version is built on the Companies Act 2006 and the 2015 trading disclosures regulations, with a company number, a registered office and the part of the UK the company sits in. Australia runs on the Corporations Act 2001 and the Business Names Registration Act 2011 instead, with an ACN, an ABN and a registered business name, administered by ASIC rather than Companies House. The identifiers, the exemptions, and even which duties apply to a company's own registered office, are genuinely different rather than translated.