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How to verify an Australian Company Number (ACN)

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Verify an ACN on the official ASIC register​

Use the Australian Securities and Investments Commission (ASIC) company and organisation registers to verify an Australian Company Number. The official entry point is ASIC's company search page.

If you need the tax-registration side of the record, see our guide to verifying an Australian Business Number (ABN). For the broader identifier context, see our Australia ABN and TFN tax ID guide.

Step 1: Open the official ASIC company register​

Go to ASIC's company and organisation registers. This is the official public register for ACN verification in Australia.

ASIC company and organisation register search screen for ACN verification
ASIC company register search

Step 2: Search by ACN, ABN, or company name​

ASIC lets you search by organisation name, registered business name, ACN, ABN, ARBN, or ARSN. Example: 001799837.

Step 3: Review the free register result​

The free result normally shows:

  • Company or organisation name
  • Type of company or organisation
  • ABN, ACN, ARBN, or ARSN
  • Registration date
  • Next review date
  • Suburb, state, and postcode of the registered office address
  • List of documents lodged with ASIC
ASIC ACN search result showing company details and registration information
ASIC ACN search result

If you need officeholder or deeper historical data, ASIC offers paid extracts below the free result.

Step 4: Validate the ACN format and check digit​

An Australian Company Number consists of 9 digits.

Regex expressionsDescription
\b\d{3}\.\d{3}\.\d{3}\bMatches a 9-digit ACN formatted with dots.
\b\d{3}-\d{3}-\d{3}\bMatches a 9-digit ACN formatted with hyphens.
\b\d{3} \d{3} \d{3}\bMatches a 9-digit ACN formatted with spaces.
\b\d{9}\bMatches a 9-digit ACN without separators.

To validate the final check digit:

  1. Remove spaces or separators.
  2. Multiply the first eight digits by [8, 7, 6, 5, 4, 3, 2, 1].
  3. Add the products.
  4. Divide by 10 and note the remainder.
  5. Subtract the remainder from 10. If the result is 10, use 0.
  6. The result must match the ninth digit.

What the ASIC result means​

  • Registered means the company is still on the register as a legal entity.
  • Strike-off in progress means ASIC has started the deregistration process.
  • Deregistered means the company no longer exists as a legal entity and cannot keep acting in its own right.

Name-mismatch checks​

If the ACN search result looks valid but the invoice still seems inconsistent:

  • Compare the ASIC legal entity name with the name on the invoice.
  • Check whether the invoice is using an ABN for a trust or another connected entity rather than the company itself.
  • Confirm any public-facing brand as a registered business name if the legal name is unfamiliar.

Frequently Asked Questions​

Why does the ASIC register show a company but ABN Lookup does not?​

ACN and ABN are different identifiers maintained by different registers. ASIC issues ACNs to companies, while the Australian Business Register issues ABNs. If you are verifying a company number, use the ASIC register first because it is the authoritative source for ACN status. ABN Lookup is useful for tax-registration checks, especially GST status, but it is not the core source for company-number verification. [1] [2]

Do I need to pay for an ASIC extract just to verify an ACN?​

Usually no. ASIC's free search already gives the organisation name, type, ACN or ABN, registration date, next review date, registered office locality, and the list of lodged documents. Buy a paid extract only when you need deeper corporate records beyond basic verification, such as officeholder details or more detailed historical data. [1]

Can a company use its ABN instead of its ACN on invoices and company documents?​

Yes. ASIC allows a company to display its ABN instead of its ACN if the ABN contains the company's nine-digit ACN and is used everywhere the ACN would otherwise be required. This is why many invoices show only the ABN even though the company still has an ACN. [1] [2]

What does "strike-off in progress" or "deregistered" mean on the ASIC register?​

"Strike-off in progress" means ASIC has started the deregistration process, commonly because annual review fees are overdue by more than 12 months. "Deregistered" means the company no longer exists as a legal entity. Once deregistered, it cannot keep carrying on business in its own right, and legal proceedings involving the company are affected. [1] [2] [3]

Can a deregistered company be reinstated after I find it on the register?​

Sometimes. ASIC allows reinstatement in limited situations, either through ASIC itself or through a court, depending on why the company was deregistered and who is applying. If reinstated, the company is treated as if it had not been deregistered. [1] [2]

This usually means you are looking at more than one identifier layer at once. The ASIC search result shows the company's legal name. The invoice may instead show a registered business name, an older trading name, or an ABN belonging to a trust that uses the company as trustee. When that happens, verify the ACN on ASIC, then separately verify the ABN and name structure on ABN Lookup before accepting the invoice as fully checked. The ABR also notes that trading names are historical only and no longer updated, which is another reason an invoice name may not match what you expect from a live register search. [1] [2] [3]

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