An AI phone agent at an Australian accounting firm may book, chase and confirm. It must not collect a tax file number, interpret an ATO notice or answer a tax question. TPB(GS) 55/2026, issued 22 July 2026, leaves the registered practitioner responsible for everything the tool does.
That guidance statement and its own exposure draft, TPB(I) D62/2026, are the only artificial-intelligence entries across all five pages of the TPB policy and guidance index, checked 16 September 2026, and at two months old the final version changes the answer. Before it, a firm had to reason from the Code of Professional Conduct in section 30-10 of the Tax Agent Services Act 2009 by analogy with cloud computing. The TPB now says directly that entering client information into an AI tool can be a disclosure to a third party under Code item 6.
What can I let an AI answering service do at my accounting practice?
Three things, narrower than the vendor pages suggest: take a booking, chase a document the firm has already asked for, and read back a fact already in the firm file. Everything else on a tax-practice phone line touches an identity number, a document needing interpretation, or a question whose answer is a tax agent service.
A voice agent is plainly inside the TPB scope: its list of what AI capability or functionality includes in the provision of tax agent services names functionality that operates autonomously without continuous human intervention and may take actions on behalf of the user
. TPB(GS) 55/2026 then says practitioners are still ultimately responsible for the tax agent services they provide to their clients
and that AI models may hallucinate or provide inaccurate information and as such cannot be relied on as a replacement for tax knowledge, experience or expertise
. No configuration screen moves that to a vendor.
The boundary: three things the agent must never do on the call
1. It must not collect a tax file number. The Privacy (Tax File Number) Rule 2015 is issued under section 17 of the Privacy Act 1988, and the OAIC states that it is legally binding
and that a breach of the TFN Rule is an interference with privacy under the Privacy Act
. A TFN recipient is any entity in possession or control of a record containing TFN information, lawfully or not, and the OAIC names accountants as approved recipients. Sections 8WA and 8WB of the Taxation Administration Act 1953 add offences for unauthorised requests, recording, use or disclosure of a TFN.
The recording problem is the one buyers miss. The OAIC guidance works through an organisation that scans correspondence incidentally containing a TFN: it would then be ‘recorded’ even if there is no intention by the agency or organisation to retain this information
. A call recording and its transcript behave the same way, so a caller who volunteers a TFN unprompted has put it into your audio store and your vendor logs, and the duty to protect and then destroy it attaches from that moment.
2. It must not interpret an ATO notice. Telling a client what a notice of assessment means is applying a taxation law to that client’s circumstances. Code items 9 and 10 put reasonable care in ascertaining a client’s affairs and applying the taxation laws correctly on the practitioner, and TPB(GS) 55/2026 attaches both to AI use. Capture the notice reference and route the call.
3. It must not give tax advice. Not a deduction, not a threshold, not even a due date, because due dates here are personal: the ATO’s page on lodging with a registered tax agent says the due date for your tax return will depend on your personal situation as well as when you engage your tax agent
. A plausible general answer to a personal question is the failure mode, and it is what a language model produces best.
The Book, Chase, Tell rule, and which rule says so
Most vendor do-not lists in this market are three prohibitions with no test attached, which is useless at three in the afternoon on 30 October. Here is the test.
The Book, Chase, Tell rule: an AI phone agent at an accounting firm may BOOK a time, CHASE a document the firm has already requested, and TELL the caller a fact already recorded in the firm file. If the call requires it to COLLECT an identity number, INTERPRET a document, or FORM a view, it stops and hands over.
Collect, interpret and form a view map one-to-one onto the TFN Rule, Code items 9 and 10, and the definition of a tax agent service. The table is our reading of the provisions in its last column, not advice about your registration.
| Caller intent | May the agent handle it | What it must do instead | Which rule makes that so |
|---|---|---|---|
| Book, reschedule or cancel an appointment | Yes | Write the booking and the call note into the firm file | Section 30 of the Code Determination |
| Chase a document the firm has already requested | Yes, chase only | Name the document and the secure channel; never accept it on the call | Section 30 of the Code Determination; Code item 6 |
| Ask whether a return has been lodged | Only as a read-back of a recorded fact | Read the file status; never infer or estimate one | Code items 9 and 10; TPB(GS) 55/2026 |
| Offer a tax file number to identify themselves | No | Verify by another identifier; do not record what was said | Privacy (Tax File Number) Rule 2015; TAA 1953 ss 8WA and 8WB |
| Read out or explain an ATO notice | No | Capture the notice reference and escalate to a registered practitioner | Code items 9 and 10 |
| Ask whether something is deductible | No | Book time with the practitioner and log the question verbatim | Code item 7; TPB(GS) 55/2026 |
| Ask what the engagement will cost | Only from a published fixed fee schedule | Refer any job that needs scoping to a person | Code item 7 |
| Raise a complaint about the firm | Log and escalate the same day | Tell the caller the TPB maintains a public register and a complaints process | Section 45 of the Code Determination |
| Any call whose audio leaves your control | Only with client permission already on file | Name the vendor, the storage location and the use of AI in the engagement letter | Code item 6; TPB(GS) 31/2018; TPB(GS) 55/2026 |
| Quote a company or trust TFN | No | Treat it the same as an individual TFN | TAA 1953 s 8WB is not written as individuals only; the TFN Rule is |
The last row catches firms that have read only the OAIC material. The TFN Rule only applies to the TFN information of individuals and does not apply to TFN information about other legal entities such as corporations, partnerships, superannuation funds and trusts
. The Taxation Administration Act is not so limited — the OAIC states that the TAA protects all TFNs, including of individuals and other entities
— so a business TFN is not a softer case.
Can it handle our tax season call surge?
It can handle the shape of the surge, which is mostly booking and chasing. Whether it is worth buying is arithmetic with one externally fixed date in it. The ATO tells taxpayers that if they are using a tax agent for the first time, or using a different tax agent, you should contact them before 31 October to be part of their lodgment program
. So the six weeks to 31 October are a hard acquisition window, and a new-client call that hits voicemail on 29 October is a client who lodges somewhere else.
Work it from your own call detail records. The values below are placeholders chosen to keep the arithmetic legible, not measurements and not industry averages. Replace all of them.
- N, inbound calls in the six weeks to 31 October last year, from your phone bill. Placeholder 900.
- a, the share your team answered, same log. Placeholder 0.72, so 252 unanswered.
- r, the share of those that were new-client enquiries, counted from voicemail transcripts. Placeholder 0.30, so 76 missed enquiries.
- c, your historical conversion of new-client enquiries, from practice software. Placeholder 0.40, so 30 clients.
- f, your own first-year fee for that client type. There is no defensible published average, so this one is yours or the sum is worthless.
The window value is N × (1 − a) × r × c × f, which on those placeholders is 30 × your fee. Then run the more useful number: take the 648 calls your team did answer and sort them by the Book, Chase, Tell rule. The share that were purely booking, chasing or reading back a recorded fact is the share an agent could carry, and it is the only figure that says whether automation buys your senior people their October back. That sort takes an afternoon with a call list and a spreadsheet, and it is the step firms skip.
Two costs belong in the same sum and are usually left out. Section 30 of the Code Determination requires records of services provided on your behalf, and TPB(GS) 52/2024 says those records must be retained for at least 5 years after the service has been provided
and include key client communications and records of discussion with the client
, so every call the agent takes is a record you now own. The other is the engagement-letter rewrite and re-consent across your client base, which is partner hours rather than software. Pricing sits elsewhere: our comparison of Australian human answering services against AI receptionists works the cost crossover, and comparing virtual receptionist options in Australia works capability by plan tier.
What changes the answer
Firm size no longer changes whether the Code Determination applies, only when it started. This is commonly reported the other way around. The TPB’s own page records that the obligations apply from 1 July 2025 – for tax practitioners with 100 or less employees as at 31 July 2024
and 1 January 2025 – for any other tax practitioners
. Both dates are past as at 16 September 2026, so a two-partner practice sits inside sections 30, 35, 40 and 45 exactly as a national firm does.
Whether your client has actually given permission. TPB(GS) 55/2026 says practitioners must obtain permission from each client prior to divulging client information to a third party (which can include entering client information into AI models and tools, depending on how these tools are configured and used)
, and recommends telling the client to whom and where the disclosure will be made, where data will be stored and whether AI tools may be used
. TPB(GS) 31/2018 adds that practitioners should require a positive step from their client to authorise the requisite disclosure
. A tick box buried in a portal is not obviously that step.
Where the audio and transcripts are stored. TPB(GS) 31/2018 lists entities that maintain offsite data storage systems (including ‘cloud storage’)
as third parties for Code item 6, and suggests that practitioners do not imply or state that all their work is completed in Australia, if that is not the case
. Speech-to-text and model inference sit in different locations from your CRM and often in different countries; ask for each by name. And permission does not cure the privacy exposure: TPB(GS) 36/2021 is explicit that obtaining the client’s permission does not override the broader privacy and security obligations of tax practitioners under the TFN Rule and APP 11
.
Do it yourself, or hand the call line over
The deny list is the product, and you can build the whole boundary above on any competent voice platform: an intent classifier that routes the three forbidden categories to a human, transcript redaction, a recording retention default in days rather than years, and a nightly export of call notes into your practice software so section 30 records exist. What it costs to run is the part vendors leave out. Somebody must own the deny list as the tax law moves, re-test it after every model or prompt change, read escalation logs weekly, and keep the consent register aligned with the vendor list. That is a standing job, not a project.
| Situation | Do it yourself | Hand it over |
|---|---|---|
| Answered-call rate in the six weeks to 31 October | Above 90 percent: fix overflow, not the platform | Below 75 percent with a rising new-client share |
| Share of calls that are pure Book, Chase, Tell | Under half: a person is already doing the valuable part | Over two thirds, sustained across the window |
| Engagement letters naming third-party disclosure and AI use | Not yet updated: do this before any vendor call | Already updated and re-consented |
| Who owns the deny list after go-live | Nobody named: do not deploy | A named person with time allocated |
Zian AI builds autonomous phone, SMS, email and WhatsApp agents, with SmartReach AI™ orchestrating message, channel and timing and PrecisionPitch AI™ split-testing scripts against real success outcomes, and supports private model deployment on customer infrastructure — which changes the disclosure you make under Code item 6, not the obligation to make one. Zian is not a registered tax agent and holds no accounting certification; no vendor here can absorb a Code obligation. The escalation and record-trail architecture sits in our note on AI sales agents in regulated industries. Adjacent verticals are separate pages: AI agents on an Australian mortgage broker file covers the best interests duty and ASIC record-keeping, and AI receptionist privacy for Australian dental and medical practices covers health information and the APPs. Neither covers TFNs or the Code.
Frequently asked questions
Can an AI phone agent collect a tax file number from a caller
No, and it should be configured so that it cannot record one either. The OAIC states that the Privacy (Tax File Number) Rule 2015 is legally binding and that a breach of it is an interference with privacy under the Privacy Act. Sections 8WA and 8WB of the Taxation Administration Act 1953 add offences for unauthorised requests for and recording of a tax file number.
Does the Tax Practitioners Board have guidance on using AI
Yes. TPB(GS) 55/2026 The use of Artificial Intelligence and the Code of Professional Conduct was issued on 22 July 2026, after an exposure draft released on 24 March 2026 whose submissions closed on 21 April 2026. It states that practitioners remain ultimately responsible for the tax agent services they provide.
Do I have to tell clients that an AI agent answers my phone
If client information reaches the vendor, yes. Code item 6 says that unless you have a legal duty to do so, you must not disclose any information relating to the affairs of a client to a third party without permission from that client. TPB(GS) 55/2026 recommends telling the client to whom and where the disclosure will be made, where data will be stored, and whether AI tools may be used.
My practice has fewer than 100 employees, so am I outside the 2024 Code Determination
No. The 100-employee test set the start date, not the scope. The TPB records that the new obligations apply from 1 July 2025 for tax practitioners with 100 or less employees as at 31 July 2024, and from 1 January 2025 for all other tax practitioners. Both dates have passed, so a small practice is fully inside the Determination as at 16 September 2026.
How long do I have to keep the call recordings
Records that evidence a tax agent service are caught by section 30 of the Code Determination, and TPB(GS) 52/2024 states the records must be retained for at least 5 years after the service has been provided. Raw audio is a separate setting: the TFN Rule requires reasonable steps to securely destroy or de-identify tax file number information once it is no longer required.
Does Zian AI provide tax or accounting advice
No. Zian AI is an autonomous sales agent platform. It is not a registered tax agent or BAS agent, holds no accounting or tax certification, and nothing here is legal, tax or compliance advice. This page summarises what the Tax Agent Services Act 2009, the Code Determination and the named guidance statements say, linked so you can read each at source.
Zian AI is in partnership-application beta, with no self-serve signup. If you run an accounting group or a practice-software business and want to work the boundary above against a real deployment, Apply For Partnership.