If you work with Australian companies, you’ll quickly come across the Australian Company Number (ACN). It’s a simple nine‑digit identifier, but it plays a big role in due diligence, everyday contracting and staying compliant with the Corporations Act.
In this guide, we’ll explain what an ACN is (and how it differs from an ABN), show you exactly how to look up a company’s ACN, and outline the key compliance rules around where your ACN should appear. We’ll also cover practical tips for using ACNs in contracts and everyday documents so you can move fast, with confidence.
Let’s get you from “what is an ACN?” to “I know exactly where to find it and how to use it” in a few easy steps.
What Is An ACN (And How It Differs From ABN)?
An ACN is a unique nine‑digit number issued by the Australian Securities & Investments Commission (ASIC) to every company registered under the Corporations Act 2001 (Cth). You’ll see it on official records for entities like “Pty Ltd” or “Ltd” companies.
It’s different to an Australian Business Number (ABN), which is an 11‑digit identifier used for tax and GST purposes across all kinds of entities (sole traders, partnerships, trusts and companies). A company will usually have both an ACN and an ABN.
- ACN: Identifies a registered company under the Corporations Act.
- ABN: Identifies a business for tax and GST across structures, not just companies.
- Company name vs business name: The ACN is tied to the legal company, which is distinct from a trading or business name. If you’re unsure, it helps to understand the difference between a business name vs company name and how an entity name works in practice.
You may also see “ARBN” (Australian Registered Body Number) for certain registered bodies and foreign companies. That’s different again from an ACN. If you’re comparing identifiers, this overview of the difference between an ABN and ARBN is a helpful starting point.
Why Your ACN Matters For Day‑To‑Day Business
For companies, the ACN is central to transparency and compliance. It also makes life easier when others are checking who they’re dealing with.
- Verification: Partners, suppliers and customers can quickly verify your status, location and ACN via ASIC.
- Clear contracting: Including your ACN alongside your full legal company name helps avoid mix‑ups with similar trading names and makes it obvious who is legally bound.
- Public record: The ACN anchors your record in ASIC’s registers, so people can confirm if the company is registered, deregistered or under external administration.
- Continuity: If your company changes its name or registered office, the ACN stays the same, providing a consistent identifier over time.
If you’re setting up a new venture and expect to deal with larger customers or investors, many founders opt to register a company from the outset so they can contract under a company’s ACN. If that’s your path, our team can assist with end‑to‑end company set up so your registrations and core documents are in place from day one.
How To Find A Company’s ACN (Step‑By‑Step)
There are a few reliable ways to find an ACN. Here’s a simple process you can follow depending on what information you have.
1) Use ASIC’s Public Register
ASIC maintains the official registers for Australian companies. The public search is free and quick.
- Go to ASIC’s “Organisation and Business Names” search.
- Enter the company’s exact name, former name (if known) or even a partial name to browse results.
- Select the correct company from the list. On the free summary page you’ll typically see the company name, status (e.g. Registered), type (e.g. Australian Proprietary Company, Limited by Shares), locality and the ACN.
Tip: The free search gives high‑level details. More detailed information (like current officeholders and historical records) usually requires purchasing an ASIC company extract.
2) Check The Company’s Own Documents
Companies are required to display their ACN on certain “public documents” and negotiable instruments (for example, formal notices, invoices and some contracts). Many businesses also display their identifier in the footer of their letterheads and standard terms, which makes it easy to confirm.
If you’ve received an invoice, purchase order or a formal contract from the company, look for “ACN” near the company name. If the company is using its ABN on those documents instead, that can generally satisfy the display requirement (more on that below).
3) Ask For It
If the ACN isn’t obvious on ASIC or recent paperwork, just ask the business to confirm it. A genuine company should have no issue providing its legal name and ACN.
4) Cross‑Check With An ABN (If You Have It)
If what you have is an ABN, you can work backwards to see if it belongs to a company and, if so, view the associated ACN. Jump to the ABN section below for steps and a quick check to check if an ABN is active.
What About Your Own Company’s ACN?
If you’ve recently incorporated, your ACN will appear on the ASIC certificate of registration and on your ASIC portal. It should also be on your invoices, letterhead and standard form agreements once you start trading. If you can’t locate it, run your own company name through the ASIC register to retrieve it.
Can You Get An ACN From An ABN?
Yes-if the ABN belongs to a company. Here’s how to check in a few minutes.
- Go to the Australian Business Register (ABR) lookup and search the ABN.
- On the ABN record, look for “Entity type.” If it’s “Australian Private Company” or similar, the record will typically display the company’s ACN alongside the ABN.
- If the entity type is “Sole Trader,” “Partnership,” “Trust” or similar, there won’t be an ACN because those structures are not companies. In that case, ask the business if they also operate through a company for contracting purposes.
Remember: a company’s 11‑digit ABN incorporates its 9‑digit ACN (with two extra digits at the front), which is why the ABR can display both for companies. If you only need to confirm that the ABN is valid and currently registered, you can check if an ABN is active using the ABR.
Compliance Essentials: Displaying Your ACN And Staying Up To Date
Once you’ve registered a company, there are a few practical rules to follow about displaying your ACN and keeping your ASIC record current.
Where Do Companies Need To Display Their ACN?
Under the Corporations Act, companies must display their ACN on certain “public documents” and negotiable instruments (for example, formal notices, invoices and some contracts). If your company has an ABN, you can usually use the ABN in place of the ACN on those documents-this is common because the ABN is often the primary identifier customers expect to see.
- Public documents: Include your ACN, or use your ABN in its place if applicable.
- Website and marketing: It’s best practice to display your company’s full legal name and an identifier (usually ABN, and many businesses include ACN as well) for transparency.
- Trading names: If you trade under a business name that’s different to the company name, make sure you display the company’s legal name somewhere clear and understand the distinction between a business name vs company name.
The exact categories of “public documents” are defined in the legislation. If in doubt, include your identifier on formal documents to avoid confusion about who the contracting party is.
Keep ASIC Records Current
Your ACN doesn’t change, but your company details might. When details change (for example, a new registered office, director change or company name), update ASIC promptly. The ACN remains the constant identifier across these updates.
Each year, ASIC issues an annual statement for your company’s review. You’ll need to confirm key details remain accurate, pass a solvency resolution and pay the annual review fee to keep your registration current. This is part of ongoing compliance rather than a separate annual “lodgement” of financials for most small proprietary companies.
If you ever need to prove registration for a tender or bank, ordering an updated ASIC certificate of registration or a current company extract can be useful.
Who Are You Actually Contracting With?
Your ACN helps clarify the legal party to a contract. If you advertise or invoice under a trading name, make sure your company’s full legal name and identifier also appear so there’s no doubt about the contracting entity. This avoids disputes and supports enforceability of your terms.
Key Legal Documents That Reference Your ACN
You’ll regularly include your ACN (or ABN) in core business documents. Having the right suite of tailored documents helps you present professionally and manage risk.
- Company Constitution: Your rules for company governance sit alongside your ACN in ASIC records and internal registers. If you’re adopting or updating one, see Company Constitution options here.
- Shareholders Agreement: If there’s more than one founder or investor, a Shareholders Agreement sets out ownership, decision‑making and exit terms, and will reference your company details and ACN.
- Customer Terms Or Service Agreements: Your standard terms should identify the correct contracting entity (full company name and ACN or ABN) so there’s no ambiguity.
- Website Policies: If you collect personal information online, a compliant Privacy Policy should clearly identify your company.
- Employment Contracts: Contracts issued to staff should use the company’s full legal name and identifier to avoid confusion with any trading name.
- Execution Blocks: When signing agreements, companies often execute under section 127 of the Corporations Act, with the company name and ACN in the signing block.
You don’t need every document on day one, but ensuring the essentials correctly identify your company helps prevent disputes and supports smooth onboarding of customers, suppliers and staff.
Key Takeaways
- An ACN is the nine‑digit number that identifies an Australian company; it’s different to an ABN, which is used for tax and GST across all business types.
- You can find a company’s ACN via ASIC’s public register, on invoices or contracts, or by looking up a company’s ABN on the ABR to see the associated ACN.
- Companies must display their ACN on certain public documents and negotiable instruments-but where a company has an ABN, using the ABN on those documents can generally satisfy the requirement.
- Keep ASIC records up to date and complete your annual review (including a solvency resolution and fee) to maintain your registration and keep your ACN active.
- Use your ACN (or ABN) consistently across contracts, invoices, websites and policy documents so it’s always clear which entity is contracting.
- If you’re forming a new company, set strong foundations with the right registrations and legal documents like a Company Constitution and Shareholders Agreement.
If you would like a consultation on ACN searches, company registration or the right documents for your business, you can reach us at 1800 730 617 or team@sprintlaw.com.au for a free, no‑obligations chat.
