FBT query emails and AI data leakage: what a client’s tax question gives away in ChatGPT or Claude.

Fringe benefits tax questions arrive as short, chatty emails from clients, and they are exactly the kind of thing staff paste into ChatGPT or Claude to get a first answer. The question itself is generic. The email around it is not: it names the employee, his weekend habits, the director’s new car and the client’s cash worries. This page marks every item in a realistic FBT query that APES 110, the TPB Code and the Privacy Act bear on, shows which questions are safe to ask anywhere, and shows how the same reply is drafted on Ermos inside the practice.

The FBT query email

Sent by a client who is about to make a decision involving a company vehicle, a staff event or a benefit, and answered by the tax agent before the decision is made.

To:
From:
Date: Wednesday 28 October 2026
Subject: FBT questions: ute, Christmas party, Priya’s car

Hi Tom,

Three quick FBT questions before I commit to anything.

I am free after 4pm on .

Daniel

An invented email. The phone number is a placeholder. Hover or tap any highlighted item for the analysis; the full list is below.

What leaves the firm

  1. 1
    The tax agent addressed

    A named registered tax agent. Ties the email to the practitioner who holds the Code obligations for this client, and to the firm, so any leak is traceable to the practice. TPB Code guide.

  2. 2
    A named employee and how he uses a vehicle

    Who has the ute, where it is kept overnight and what it carries. Personal information about an employee who is not the firm’s client. The ATO says an eligible vehicle used only for home-to-work travel, incidental travel and minor, infrequent, irregular private use can be exempt, so the facts decide. Privacy Act guide.

  3. 3
    Weekend private use

    A regular private use described by an employee’s weekend plans. This is the fact that decides the FBT answer, and it also records something about his family life. The ATO warns that employers often assume dual cab utes are automatically exempt. Privacy Act guide.

  4. 4
    A staff event with names, a venue and a cost per head

    A date, a venue, a headcount and a cost per person including partners. The ATO’s minor benefits exemption looks at cost per person and whether it is unreasonable to treat the benefit as a fringe benefit, with partners tested separately. APES 110 confidentiality guide.

  5. 5
    A director’s new car and its price

    A named person’s vehicle, the price and her use of it. The ATO’s electric car exemption has conditions, including that the car is a battery electric or hydrogen fuel cell vehicle first held and used on or after 1 July 2022, and that no luxury car tax has become payable on the car, so the price and model matter. Privacy Act guide.

  6. 6
    An admission that no FBT return was ever lodged

    The client’s own statement of a possible compliance gap. The ATO lists private use of work vehicles as a focus area for small business, so the sentence is the one most damaging if it reached anyone else. TPB Code guide.

  7. 7
    A personal phone number and call time

    Contact details for an individual, with a preferred time to reach him. Privacy Act guide.

  8. 8
    The sender and his business

    A named director at a named company. The key that ties every other line to a real business and real people. APES 110 confidentiality guide.

  9. 9
    The cash worry and the wish to avoid FBT

    The client’s financial position and what he hopes to save. The ATO publishes the FBT rate as 47% for the year ending 31 March 2027, applied to the grossed-up taxable value, so the client’s worry is about real money. The firm’s reply is advice, and the client’s remark about wanting to avoid the tax is part of the file. TPB Code guide.

  10. 10
    The generic questions

    Whether private use of a ute is exempt from FBT, and whether the $300 minor benefit rule applies. Public rules the ATO explains, with no client in the wording.

What happens in Frontier Models (ChatGPT, Claude)

  • The whole document is transmitted to the provider’s servers. On personal plans the user cannot choose where it is stored or processed, and for the major providers that has generally meant outside Australia, under that country’s legal process. Some business plans offer storage in Australia, but the provider still receives the content.
  • On consumer tiers, prompts can be retained and used to train future models.
  • The provider’s staff and systems can reach the content under the provider’s own policies.
  • Once sent, the firm no longer controls it. Retention and deletion happen on the provider’s terms.

The same document on Ermos

Ermos Dominion

The document is drafted on a unit in your office, from your own templates and the client file. Every marked item stays on the unit, which keeps working with the internet switched off. Nothing in it is transmitted to an AI provider, so there is no disclosure to analyse: the confidentiality work is the same as for your file server.

Ermos Edge

Your documents, the index and your access boundaries stay on your own instance in an Australian data centre. When a staff member asks for this draft, only their question and the excerpts they are permitted to see go to a named Australian provider, who is contractually barred from keeping the content or training any model on it. Nothing is processed outside Australia.

Frontier Models (ChatGPT, Claude)Ermos EdgeErmos Dominion
Where the document is processedProvider servers, generally offshore on personal plansYour instance in an Australian data centre; answers generated in AustraliaThe unit in your office
Who can read itProvider staff and systems, under policyYour staff, within the boundaries you set. The named Australian provider processes only permitted excerpts, under contract, and keeps nothingYour staff only
Is it keptOn the provider’s termsKept on your instance; the provider is barred from retaining itStays on the unit
Can it train a modelOn consumer tiers, yesNo, by contractOnly your own unit learns from it, on your hardware

Part of AI data leakage in accounting firms. See how this works in practice: Client correspondence on Ermos.

Common questions

Do ChatGPT and Claude use the information in an FBT query email?
Yes, the email goes to the AI company's servers and is processed there to produce a reply, whether it is pasted or attached. As at October 2026, whether a conversation on a personal plan (ChatGPT Free, Plus or Pro; Claude Free, Pro or Max) can be used to train the models depends on a setting each user controls. Business plans (ChatGPT Business and Enterprise, Claude Team and Enterprise) and the developer APIs sit under commercial terms, and OpenAI and Anthropic each say they do not train on that content by default (OpenAI, Anthropic). On either product, the thumbs up and thumbs down buttons can send a whole conversation back for training. This email gives Marcus Hale's weekend use of the ute, a director's new car at $68,500 and the client's doubt that an FBT return was ever lodged.
Can we use ChatGPT or Claude for an FBT query email if we ask only the generic question?
The generic question is fine to ask anywhere, but the email around it is not. The ATO's rules on utes, the $300 minor benefit and electric cars are public and contain no client data. The Office of the Australian Information Commissioner (OAIC) recommends in its guidance on commercially available AI products that organisations do not enter personal information, and particularly sensitive information, into publicly available generative AI tools, because of the significant and complex privacy risks. The email adds a named employee, Priya's car, the client's cash worries and a personal phone number. Pasting the whole email sends all of that with the question.
Does deleting the chat remove an FBT query email from ChatGPT or Claude?
Not on its own, because the user's history is only part of the picture. Deleting a chat removes it from the user's history, but OpenAI and Anthropic each say they can keep a deleted chat on their systems for up to 30 days, and longer where safety or legal obligations apply (OpenAI, Anthropic). Both products also have memory features that can carry details from one conversation into later ones, and on a personal account each user decides whether they are switched on (ChatGPT, Claude). For this email, the client's remark about never lodging an FBT return and wanting to avoid the tax could still be on the AI company's systems after the user has cleared their history.
How can an accounting practice use AI for an FBT query email without sending it to ChatGPT or Claude?
Ermos is built so the document stays under your control. On the Dominion AI unit it is drafted inside your office and none of it is sent to an AI provider. On Ermos Edge your documents and index stay on your own instance in an Australian data centre, and only the question and the excerpts the user is permitted to see go to a named Australian provider that is contractually barred from keeping them or training any model on them. Ermos drafts the reply from the client file and the practice's own FBT letter template. The tax agent checks the facts against the ATO's current rules and signs it before it goes to the client.
Is a ute with private use always exempt from FBT?
No. The ATO says an employee's use of an eligible vehicle, such as a ute, can be exempt if it is limited to travel between home and work, travel incidental to duties and private use that is minor, infrequent and irregular. A dual cab may not be eligible, and regular weekend use can take it outside the exemption. The employer needs to be able to show the limits were kept.
What does the ATO say about Christmas parties?
Food and drink at a party held on business premises on a working day and consumed by current employees is generally exempt. For a party elsewhere or one that includes partners, the minor benefits exemption can apply where the cost per person is under $300 and it would be unreasonable to treat the benefit as a fringe benefit. Each person is tested separately.
Can the reply to an FBT question be drafted with AI?
Yes, but the client's email names an employee, a director's car and the client's cash position, all of which are information about the client's affairs. For a registered tax agent or BAS agent, TPB Code item 6 requires the client's permission before such information goes to a third party unless there is a legal duty to disclose it, and TPB(GS) 55/2026 recommends telling the client where data will be stored and whether AI tools may be used.

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