How to Update Your ABN Details in 2026: The 28-Day Rule, Addresses, Associates and Business Activities

Your ABN isn't a set-and-forget registration. Every time your business moves, changes directors or partners, adds a new line of work or changes its phone number, the Australian Business Register expects to hear about it — and the clock is short. This guide is for sole traders, partnerships, companies, trusts and not-for-profits. It explains which details you must keep current, how to change them online in a few minutes, what the ABR won't let you change, when a change means a new ABN rather than an update, and how the ABR and ASIC registers fit together, with worked examples.

Quick answer

You must update your ABN details within 28 days of becoming aware of a change. The fastest way is ABR online services: sign in with your Digital ID (such as myID) linked to the business in Relationship Authorisation Manager, choose Update ABN record, make the change and submit — it takes effect immediately. You can also ask your tax or BAS agent, phone the ABR on 13 92 26, or post the Change of registration details form.

• Business address must be a street address — not a PO box or your agent's address

• Keep associates (directors, partners, trustees, public officer) current

• Add up to 4 extra business activities beside your main one

• Business names, company names and entity type can't be changed on the ABR

• A new structure (e.g. sole trader to company) usually needs a new ABN

Why your ABN details matter

The ABR holds two kinds of information about you. Some of it is public and appears on ABN Lookup: your ABN and its status, legal name, entity type, GST registration, registered business names, and the state and postcode of your main business address. The rest is non-public: your associates, your business activity code, the full business address and its map location, your postal address for notices, phone numbers and authorised contacts. Government agencies can use parts of the non-public record.

That's why the ABR asks you to keep it current. Correct details make sure the right people have authority to act for the business, let agencies contact you — including emergency services and disaster recovery programs that use business locations to target help — and keep your ABN Lookup listing accurate for customers checking you out.

Updating is also how you avoid penalties. The ABR can penalise false or misleading statements, but it says you may not be penalised if you correct your details before it contacts you, or if you took reasonable care and made an honest mistake.

What you must keep up to date

The rule is broad: any change to the details on your ABN record must be notified within 28 days of you becoming aware of it. In practice, the changes that come up most are:

Changes to GST — reporting cycle, accounting method or cancelling registration — are made with the ATO through Online services for business or your agent rather than as an ABN detail. If you're closing down, see our guide to cancelling an ABN.

How to update your ABN details online

ABR online services is the quickest route, and changes made there take effect immediately. You sign in with a Digital ID such as myID, and your ID must be linked to the business through Relationship Authorisation Manager (RAM). A sole trader links their own ABN; for a company, partnership or trust, an associate with authority — usually a director, partner or trustee — sets up the link and can authorise employees or others.

Update your ABN record online

1. 1

   Set up myID and RAM

   Get a myID at Standard strength or higher, then link it to the business in Relationship Authorisation Manager.

   Tip: Already linked for ATO Online services for business? The same link works for the ABR.

2. 2

   Log in to ABR online services

   Choose Continue with Digital ID, then select Update ABN record.

   ABR — Update your ABN details
3. 3

   Pick the section to change

   Business address, postal address, additional locations, contact details, associates, or ANZSIC and business details.

4. 4

   Make the change

   Enter the new details. For associates, you'll need each person's name, date of birth, position and TFN or residential address.

5. 5

   Declare and submit

   Tick the declaration and submit. The change applies straight away — check ABN Lookup to confirm public details.

If you can't use ABR online services

You have three other options. Your registered tax or BAS agent can update your details through their own online services. You can phone the ABR on 13 92 26 on weekdays. Or you can complete and post the Change of registration details form (NAT 2943). Paper is the slowest route: for not-for-profits using the form, the ABR says it tries to process within 28 days but you should allow 5 to 12 weeks for confirmation.

Not-for-profits often hit a particular snag: the volunteer who was the authorised associate has left and nobody else can log in. A current associate can update the record online or by phone. A newly appointed associate whose predecessor is unknown or can't be contacted can notify the ABR only on the paper form, and must include evidence of the appointment, such as the meeting minutes or a board notice recording it.

Addresses: business, postal and additional locations

The ABR treats addresses carefully because they feed into emergency and disaster programs. Your main business address must be the physical street address where your business or organisation operates. It can't be a post office box, and it can't be your tax or BAS agent's address. If you work from home, that's your home address — and only the state and postcode appear publicly on ABN Lookup.

Your postal address is where the ATO and ABR send notices. This can be a PO box, your agent's office, or the business address. If you trade from more than one place — two shops, a workshop and a market stall, or several offices — add each street address as an additional location. The ABR asks every ABN holder to check these details even if nothing has changed since they registered, because older records often hold only a mailing address.

When you move, remember that the ABR is one of several registers. If you hold a business name, ASIC also has your business name addresses and needs them updated within 28 days. A company has a registered office and principal place of business with ASIC that must also be updated within the same period. Councils, licensing bodies, insurers and your bank all need to know too.

The three ABR address fields

Field	What it must be	PO box or agent allowed?	Shown on ABN Lookup?
Business address	Street address where the business operates	No	State and postcode only
Postal address	Where you want ATO and ABR letters sent	Yes	No
Additional locations	Street address of each other site	No	No

Business address

What it must be

Street address where the business operates

PO box or agent allowed?

No

Shown on ABN Lookup?

State and postcode only

Postal address

What it must be

Where you want ATO and ABR letters sent

PO box or agent allowed?

Yes

Shown on ABN Lookup?

No

Additional locations

What it must be

Street address of each other site

PO box or agent allowed?

No

Shown on ABN Lookup?

No

Associates: directors, partners, trustees and public officers

Associates are the people and organisations behind the entity. Which associates you must list depends on the structure. A private company lists its directors, its public officer and, where relevant, its top 20 shareholders for each class of share. A partnership lists its partners. A trust lists its trustee — and a closely held trust also lists its top 20 beneficiaries. Other incorporated bodies list their directors or office bearers and a public officer, and self-managed super funds list members and trustees.

For each individual associate you give their name, date of birth, position and either their TFN or residential address. For organisations you give the legal name, an identifier such as an ACN or ABN, and either a TFN or address and date of formation. The details of resident associates must match ATO records — if they don't, the change can be rejected, so check spelling and dates of birth carefully.

Associates matter for more than paperwork. An associate listed on the ABR can set up RAM authorisations and speak for the entity, so a former director or partner left on the record still has a pathway to act for your business. Removing departing associates promptly is a basic security step.

Business activities and ANZSIC codes

Your ABN record carries a main business activity, classified with an ANZSIC (Australian and New Zealand Standard Industrial Classification) code. You can now also register up to 4 additional business activities. The ABR's own example is a winery: its main activity is wine manufacturing, and it can add liquor retailing, accommodation, cafés and restaurants, and a short-distance tour bus service.

To add one, log in, choose Update ABN record, then ANZSIC and business details and Additional business activity. Type a short description of the activity, choose the category that matches best, and the ANZSIC code fills in automatically. Repeat for each activity, then declare and submit.

Keeping activities current is more than housekeeping. Government programs, including disaster assistance, use industry codes to identify affected businesses, and statistics agencies use them to measure industries. If your record says café but you now only do consulting, update it.

What you can't change on the ABR

Some details can't be changed through ABR online services or the change form:

• Entity type. Contact the ATO; see the next section on structure changes.
• Business names. Register, change or cancel them with ASIC; the ABR updates automatically.
• Trading names. The ABR stopped collecting unregistered trading names when the national business names register started in 2012, and the old ones were shown on ABN Lookup only until 31 October 2025. If you trade under a name that isn't your own legal name, register it as a business name.
• Legal names of individuals and sole traders. Contact the ATO directly; once the ATO updates your name, the ABR follows.
• Legal names of ASIC-registered companies. Change the name with ASIC; the ABR follows.

Your yearly ABN record check

0/6

• Business address is the street address where you operate
• Postal address and email still reach you
• Phone numbers and authorised contacts are current staff
• Associates match your current directors, partners, trustees or public officer
• Main and additional business activities match what you do now
• RAM authorisations removed for anyone who has left

Share Print

Review the record once a year — at tax time is easy to remember — and whenever you move, change directors or partners, or start a new line of work. A yearly review catches the slow drift that nobody notices: a mobile number that belonged to a former employee, a postal address at an accountant you no longer use, or a public officer who retired. Those are exactly the details the ATO and ABR rely on when they need to reach you about a lodgement, an integrity check or a disaster support program, so out-of-date contacts can mean missed letters and deadlines.

Changing structure: update or new ABN?

An ABN belongs to an entity. If the entity changes, you usually need a new ABN rather than an update. The ABR's examples of changes that need the old ABN cancelled and a new one issued are: sole trader to partnership, partnership to company, sole trader to company, and a company or other entity to a trust. Taking on a business partner as a sole trader is therefore not an associate update — it creates a new partnership entity.

A few changes let you keep the same ABN: a private company becoming a public company or vice versa, a company becoming an Aboriginal and Torres Strait Islander corporation, and an incorporated association becoming a public company limited by guarantee. These can't be done online or on the change form; you contact the ATO to have the entity type reviewed. In very limited cases the Registrar will also correct an entity type chosen by mistake at registration, if you provide evidence such as incorporation documents.

When you do get a new ABN, update your invoices, website, email signatures, contracts, supplier accounts and payment platforms, register the business name to the new entity if needed, and transfer GST, PAYG and other registrations. Our ABN registration guide covers applying again.

Is it an update or a new ABN?

Step 1

Something changed

Step 2

Same entity?

address, contacts, associates, activities

Step 3

Update within 28 days

ABR online services

Step 4

New entity?

sole trader → company, etc.

Step 5

Cancel old ABN, apply for new

update invoices

Worked examples

A sole trader's café moves

Mia runs a café as a sole trader in Newtown and moves to a bigger shop in Marrickville on 1 March. By 29 March she logs in to ABR online services, changes her business address to the new street address, keeps her PO box as her postal address, and updates her phone number. Because she trades under a registered business name, she also changes the business name addresses in ASIC Connect within 28 days. She tells the council (food business registration), her insurer and her bank. ABN Lookup still shows NSW, but with her new postcode.

A company changes directors

A private company replaces one of its two directors. The company notifies ASIC of the resignation and appointment on Form 484 within 28 days, and the new director already has a director ID. Separately, a remaining director logs in to ABR online services, removes the former director as an associate and adds the new one with their date of birth, position and TFN. The departing director's RAM authorisation is removed the same day so they can no longer act for the company.

An electrician adds solar installation

An electrical contractor starts installing solar panels and batteries alongside general electrical work. The main activity stays as electrical services, and the business adds solar installation as an additional business activity with its ANZSIC code. Nothing else changes, so there's no new ABN and no change to GST.

A sole trader takes on a partner

Josh, a sole-trader landscaper, goes into business with his brother as equal partners from 1 July. That's a new entity: the partnership applies for its own TFN and ABN, registers for GST if its turnover will reach A$75,000, and transfers the business name. Josh cancels his sole-trader ABN if he no longer runs a separate business, or keeps it if he still does other work in his own name.

The four examples side by side

Change	ABR action	ASIC action	New ABN?
Café moves	Business address, phone	Business name addresses	No
Company changes director	Associates; RAM authorisations	Form 484	No
Adds solar installation	Additional business activity	None	No
Sole trader takes on partner	New partnership ABN	Transfer business name	Yes

Café moves

ABR action

Business address, phone

ASIC action

Business name addresses

New ABN?

No

Company changes director

ABR action

Associates; RAM authorisations

ASIC action

Form 484

New ABN?

No

Adds solar installation

ABR action

Additional business activity

ASIC action

None

New ABN?

No

Sole trader takes on partner

ABR action

New partnership ABN

ASIC action

Transfer business name

New ABN?

Yes

Common mistakes

Using a PO box or accountant's office as the business address. Fix: enter the street address where the business operates and put the PO box in the postal address.

Updating ASIC but not the ABR. ASIC's company register and the ABR are separate except for names. Fix: update associates and addresses on both.

Leaving a former director or partner as an associate. Fix: remove them and their RAM authorisations as soon as they leave.

Treating a new structure as an update. Fix: if the entity changes, apply for a new ABN and update every document.

Forgetting the 28-day clock. Fix: make "update the ABR" part of your checklist for every move, hire of a public officer or board change.

Official links

• ABR — Update your ABN detailsOnline, phone, agent or form
• ABR — Changing your business structureWhen you need a new ABN
• ABR — Associates' detailsWho to list for each entity type
• ASIC — Change business name holder detailsBusiness name changes within 28 days
• ASIC — Change company officeholder detailsForm 484
• ABN LookupCheck your public details

What to do next

Log in to ABR online services today and check your business address, postal address, associates and activities — even if nothing has changed, older records often need tidying. Then check how you appear on ABN Lookup, update your invoices with our invoice generator if anything changed, and read who is entitled to an ABN if your activities have shifted.

This is general information, not legal or tax advice — confirm on the official source or with a professional.

Frequently asked questions

How long do I have to update my ABN details?

The ABR says you must update your details within 28 days of becoming aware of a change. That covers things like a new business address, postal address, phone or email, a change of directors, partners or trustees, or a change in your business activities. Changes you make online through ABR online services take effect immediately.

How do I change my ABN address?

Log in to ABR online services with your Digital ID (such as myID) linked to the business through Relationship Authorisation Manager, select Update ABN record, then Business address and Postal address. The business address must be the street address where the business operates, not a PO box or your accountant's address; your postal address can be either. Submit the declaration and the change applies immediately.

Can I change my business name on my ABN?

Not through the ABR. Business names are registered with ASIC, so you register, change or cancel them through ASIC Connect, and the change flows through to the ABR automatically. The same applies to a company's legal name. A sole trader's legal name change goes through the ATO. The ABR stopped recording unregistered trading names in 2012.

Do I need a new ABN if I change my business structure?

Usually yes. Moving from sole trader to partnership or company, partnership to company, or company to trust means a new entity, so you cancel the old ABN and apply for a new one, then update your invoices and documents. A private company becoming a public company can keep its ABN. Entity type changes can't be made online — contact the ATO.

Is there a penalty for not updating my ABN details?

The ABR can apply penalties for false or misleading statements about your ABN, but it says you may not be penalised if you correct your details before it contacts you, or if you took reasonable care. Out-of-date details also cause practical problems: letters go astray, clients see wrong information and emergency or disaster support may not reach you.

Who can update ABN details?

An associate with authority in Relationship Authorisation Manager — such as the sole trader, a director, partner or public officer — can update details in ABR online services, as can your registered tax or BAS agent. You can also phone the ABR on 13 92 26 or post the Change of registration details form. A new associate of a not-for-profit whose predecessor can't be contacted uses the paper form with proof of appointment.

Sources & verification

Figures on this page were checked against the sources below when it was last reviewed on 12 October 2026. Each rate and limit is stored once with its own official source and review date, and official update channels are monitored daily so changes are picked up. How we verify

1. 1.Update your ABN details — Australian Business Register · accessed 12 October 2026
2. 2.Changing your business structure — Australian Business Register · accessed 12 October 2026
3. 3.Associates' details — Australian Business Register · accessed 12 October 2026
4. 4.Your ABN details on the ABR — Australian Business Register · accessed 12 October 2026
5. 5.Trading names in the ABR — Australian Business Register · accessed 12 October 2026
6. 6.Making a false or misleading statement — Australian Business Register · accessed 12 October 2026
7. 7.Contact the ABR — Australian Business Register · accessed 12 October 2026
8. 8.Change business name holder details — ASIC · accessed 12 October 2026
9. 9.Change a business name address — ASIC · accessed 12 October 2026
10. 10.Change company officeholder details — ASIC · accessed 12 October 2026