Can You Change Your ABN? Rules and When You Need a New One

Thinking about “changing your ABN” usually means one of two things for a small business: you’re either updating the details attached to your current Australian Business Number (ABN), or you’re moving your operations to a different legal entity (which requires a new ABN).

It’s an important distinction. In Australia, an ABN is attached to a legal entity (like a sole trader, partnership, company or trust) - not to a brand name or trading activity. So while you can update details on an existing ABN, you can’t simply swap an ABN from one legal entity to another.

In this guide, we’ll explain when you can keep your ABN, when you need a new one, and how to manage the legal and practical steps if you’re moving your business to a new entity. We’ll also cover the key documents and contracts to update so you can stay compliant and avoid disruption to cash flow.

What Does It Mean To “Change” An ABN?

Let’s clear up the language first. ABNs are issued by the Australian Business Register (ABR) to a specific legal entity. You can:

• Update your existing ABN’s details (for example, your business name, trading name, addresses, business activities or authorised contacts).
• Cancel your current ABN if you stop that entity’s business activities.
• Apply for a new ABN if the underlying legal entity that runs your business changes (for example, switching from sole trader to company).

So, you don’t “change” a number into another number. You either maintain the same ABN for the same entity and keep its details up to date, or you get a new ABN for a new entity.

If you’re unsure how ABNs work and why they matter for invoicing, GST and contracting, it’s worth revisiting the basics of an ABN before you make structural changes.

When Do You Need A New ABN?

You’ll need a new ABN when the legal entity behind your business changes. Common scenarios include:

Switching From Sole Trader To Company

If you’ve outgrown your sole trader setup and want limited liability, investor readiness or a clearer separation between you and your business, moving to a company is a common step. A company is a separate legal entity with its own obligations and taxes, so it must have its own ABN.

That means your sole trader ABN stays with you as an individual, and your new company receives a new ABN. If incorporating is on your roadmap, consider getting help with Company Set Up so the constitution, share structure and registrations are done correctly from day one.

Starting Or Ending A Partnership

A partnership is its own ABN-holding entity (separate from the partners personally). If you form a new partnership, you’ll apply for a new ABN. If a partner leaves or a new one joins, you may need to cancel the old partnership ABN and set up a new one, depending on the change.

Moving To Or From A Trust

Trusts (through their trustee) also hold an ABN. If you restructure your business to operate through a trust, or you change the trustee in certain ways, you’ll likely be applying for a new ABN.

Buying Or Selling A Business

When you purchase a business, you typically buy its assets (not its ABN). Your entity uses its existing ABN to run the newly acquired business. The seller keeps their ABN for their entity. If you’re dealing with a full entity purchase, that’s a different transaction - but the ABN still stays with the entity, not the business name.

In all these cases, remember that a new entity means a new ABN, fresh tax registrations as needed, and updates to your contracts, invoices and systems.

Can You Keep Your ABN And Just Update Details?

Yes, if the underlying legal entity remains the same, you can keep your ABN and update its details through the ABR. Typical updates include:

• Changing or adding a trading name (noting that business name registration with ASIC is separate)
• Updating your business address or postal address
• Adding new business activities or changing your industry description
• Updating authorised contacts or associates

You should keep these details current to avoid delays with tax and government correspondence and to ensure your invoices and public listings are accurate.

If the entity has stopped trading entirely, you can cancel the ABN. If you’re wondering about timing or whether ABNs lapse, it’s useful to understand what happens and whether an ABN expires in different scenarios.

Step-By-Step: Moving Your Business To A New ABN (New Entity)

If you’re restructuring (for example, moving from sole trader to company), the goal is to move operations with minimal disruption. Here’s a practical roadmap.

1) Set Up The New Entity

Incorporate the company or establish the new structure, then obtain the new ABN and any tax registrations (GST, PAYG withholding, fuel tax credits, etc.). Make sure your company has a fit-for-purpose governance framework, including a Company Constitution, and if there’s more than one founder or investor, a Shareholders Agreement to set out roles, decision-making and exits.

2) Plan The Transfer Of Assets And Contracts

Decide which assets the new entity will take over: domain names, websites, equipment, inventory, customer lists, supplier relationships and IP (brand, content and software). You can transfer assets via a bill of sale or a business sale process between the old and new entities. Where you need customers or suppliers to formally recognise the new entity, use a Deed of Novation so existing contracts continue seamlessly with the new entity.

If you’re leasing premises, moving the tenancy often requires landlord consent and a formal Deed of Assignment of Lease. Get ahead of this early, as landlords and lenders can take time to approve changes.

3) Consider A Business Sale Agreement Between Entities

Even when you “own both sides”, documenting the transfer helps with clarity, taxation and financing. A formal Business Sale Agreement can record what is moving, the price (if any), completion date, employee transfers, apportionment of liabilities and post-transfer obligations.

4) Update Finance, Tax And Banking

Register the new entity for GST if your turnover is or will be above the threshold, set up PAYG withholding if you’ll have employees, and update bank accounts. Let your accountant know the transfer date so invoicing and BAS reporting don’t overlap incorrectly between entities.

5) Communicate With Customers And Suppliers

Share your new ABN, invoicing details and bank account. Provide updated invoices and, where necessary, new or novated contracts. If you run subscriptions or long-term services, plan a clean changeover so direct debits and renewals continue without interruption.

6) Align Your Website, Policies And Templates

Update invoice templates, quote templates and your website footer with the new entity’s details. If you sell goods or services, refresh your Terms of Trade so they name the new entity as the contracting party. If you collect personal information, ensure your Privacy Policy properly identifies the new entity and reflects your current data practices.

7) Close Out The Old Entity’s Obligations

Finalise outstanding invoices and liabilities in the old entity, lodge final returns, and consider cancelling tax registrations that are no longer needed. If the old entity will stop trading altogether, you can cancel its ABN once obligations are complete.

Tip: Timing matters. Pick a clear “handover” date so your team knows which ABN to use for sales, purchases and payroll from that day forward.

What To Update After An ABN Change

Whether you’ve updated details for the same ABN or moved to a new entity and new ABN, work through this checklist to avoid missed payments or compliance issues.

Invoices, Quotes And Payment Systems

• Update your invoice and quote templates with the correct legal name, ABN and contact details.
• Check payment gateways (Stripe, PayPal, direct debit) to ensure the legal entity and settlement bank accounts are correct.
• Notify regular customers of the new billing entity and ABN before the next billing cycle.

Contracts And Terms

• Replace or novate existing contracts so the new entity is the named party.
• Refresh your website terms, online checkout terms or Terms of Trade so they match the new entity details.
• Update supplier agreements, distribution agreements and SaaS subscriptions to avoid disputes about who owes what.

Licences, Permits And Insurance

• Some licences and permits are entity-specific. Check transfer or re-issue requirements with the relevant authority.
• Update insurance policies (public liability, product, professional indemnity, cyber) to the new entity.

Website, Marketing And Public Listings

• Update your website footer, contact page and policy pages to the correct legal entity and ABN.
• Refresh email signatures, proposals, letterheads and templates.
• Update Google Business Profile, social media bios and directories with the correct entity details.

Employment And Payroll

• Set up payroll and superannuation under the new entity if you’ve restructured.
• Issue new Employment Contract letters if required, or confirm in writing that employment has transferred on existing terms (check awards and Fair Work obligations).

Tax And ATO Registrations

• Review GST registration, PAYG withholding and fuel tax credits registrations to ensure they match the correct ABN.
• Coordinate BAS periods so returns are filed by the correct entity and there’s no double-reporting.

If you methodically work through these updates, the transition should be smooth for customers, staff and suppliers.

Key Legal Documents To Get Right

Restructuring or refreshing your ABN is also the perfect time to audit your legal documents. The right set of contracts reduces risk and keeps cash flow steady.

• Terms of Trade: Standard terms for sales and services that set payment terms, liability, warranties and deliverables - ensure they name the correct entity and ABN. Consider including late fees and strong limitation of liability language.
• Customer Contract: If you provide bespoke services or projects, a tailored service agreement helps avoid scope creep and disputes.
• Privacy Policy: If you collect personal information (web forms, checkout, mailing lists), your Privacy Policy must accurately identify the entity responsible and explain how you handle data.
• Website or App Terms: If you sell online or operate a platform, make sure your terms are aligned with the Australian Consumer Law, your refunds process and your entity details.
• Deed of Novation: Use a Deed of Novation to move existing customer or supplier contracts from your old entity to the new one without losing continuity.
• Deed of Assignment of Lease: If you operate from leased premises, a Deed of Assignment of Lease and landlord consent are typically required to transfer the lease.
• Business Sale Agreement: Documenting an internal asset transfer with a Business Sale Agreement helps with clarity on assets, liabilities and completion processes - even if both entities are under your control.
• Employment Contracts & Policies: Ensure your contracts name the right employer entity and that your policies reflect your current operations and Fair Work obligations.
• Shareholders Agreement: If you have co-founders or investors in a company, a Shareholders Agreement sets out ownership, decision-making, vesting and exits - crucial when you’re investing in a new structure.

If you’re also refreshing your brand or product lines as part of the transition, consider protecting your brand with trade marks and reviewing any licences or distribution arrangements for the new entity.

Key Takeaways

• You can’t “change” an ABN from one entity to another - you either update details on the same ABN or apply for a new ABN when the legal entity changes.
• Common triggers for a new ABN include moving from sole trader to company, starting or ending a partnership, or operating through a trust.
• If you restructure, plan a clean transfer of assets, contracts and leases, often using a Deed of Novation or Deed of Assignment of Lease, and consider documenting the transfer with a Business Sale Agreement.
• Update invoices, systems, tax registrations, website details and policies so customers and suppliers have the correct legal name and ABN.
• Refresh key documents like Terms of Trade, Privacy Policy and Employment Contracts so they properly identify the new entity and keep you compliant.
• Getting the new entity’s foundations right from day one - including Company Constitution and governance agreements - reduces risk and sets you up for growth.

If you’d like a consultation about moving your business to a new ABN or setting up the right legal documents for your transition, you can reach us at 1800 730 617 or team@sprintlaw.com.au for a free, no-obligations chat.