AI BAS/GST Explanation Templates for Australian Accountants

Every quarter, the same conversation. A new client — often a recent migrant running a café, import business or cleaning service — sits across from you and asks: "What exactly is this BAS thing I need to lodge?"

That conversation takes 30 to 60 minutes the first time. You explain GST. You explain PAYG. You explain why they owe money they didn't know they owed. You explain the due dates. You do it again next quarter because they forgot. You do it again for the next new client.

AI cannot do your tax work. But it can give you a library of plain-English explanations you customise in 2 minutes and send before the client even calls — so the phone call is about their specific situation, not the basics.

Here are five prompt templates that handle the conversations you have most often.

1. What BAS actually is — the quick version

A Business Activity Statement is the ATO's quarterly reporting form for business tax obligations. It pulls together three things that most new clients don't realise are connected:

• GST (Goods and Services Tax): 10% added to most sales. You collect it from customers, pay it to the ATO, and claim back GST on your business expenses. Net amount goes on the BAS.
• PAYG Withholding: If you have employees, you withhold tax from their wages each pay cycle and report/remit it via BAS.
• Fuel Tax Credits: Eligible businesses (construction, transport, farming) can claim credits for fuel used in certain off-road or business activities — often missed by first-time filers.

Quarterly due dates: 28 October (Q1 Jul–Sep), 28 February (Q2 Oct–Dec), 28 April (Q3 Jan–Mar), 28 July (Q4 Apr–Jun). Tax agent lodgement extensions typically apply if you lodge on the client's behalf.

That's the factual context. Now here's how to explain it to a client without spending an hour on it.

2. Five prompt templates — copy, adapt, send

Each template below is a skeleton you paste into ChatGPT (or Claude, or Gemini). Replace the bracketed fields with context specific to your client. Review the output before sending — more on why that matters in section 4.

2.1 Explaining what BAS is to a brand-new client (first lodgement)

Use this when a client has never lodged a BAS before — common with recent migrants who have just registered an ABN.

Write a plain-English email explaining what a Business Activity Statement (BAS) is, for a [type of business, e.g. café owner / cleaning service / import trader] who has just registered an ABN and has never lodged a BAS before. Assume they have some business experience but no knowledge of the Australian tax system. Cover: what BAS is, why they need to lodge it quarterly, what GST means for their business, and what happens if they miss the due date. Keep it under 300 words. Friendly but professional tone. Do not include any specific dollar figures or dates — I will add those manually.

2.2 Explaining why their GST refund is lower than expected

One of the most common difficult conversations: the client expected a refund, you're telling them it's smaller than last quarter (or they actually owe). Use this to draft a pre-call briefing note.

Write a brief, plain-English explanation (150 words max) of why a small business owner's GST refund might be lower this quarter compared to last quarter, even if their revenue stayed similar. List the three most common reasons: higher taxable sales mix, lower claimable business purchases, and timing of large one-off input tax credits in a prior quarter. Do not use accounting jargon. Frame it as a factual explainer, not an apology. I will personalise it with the actual reasons before sending.

2.3 Explaining PAYG withholding to a client who just hired their first employee

The moment a client hires staff, their BAS changes. Many small business owners — especially those used to sole-trader operation — don't realise PAYG withholding is reported on the same form.

Write a plain-English explanation for a small business owner who has just hired their first employee and doesn't understand what PAYG withholding is or why it appears on their BAS. Explain: what PAYG withholding is, that they are required to withhold tax from employee wages and remit it to the ATO each quarter via BAS, and that this is separate from Superannuation (which is not on BAS). Keep it under 200 words. Avoid acronyms where possible — spell them out the first time. I will review and add the specific withholding amounts separately.

2.4 Explaining the $75,000 GST registration threshold to a growing business

Use this when a sole trader or small business is approaching the threshold and needs to understand what changes — and when — without panicking.

Write a plain-English explanation of the Australian GST registration threshold for a small business owner whose annual turnover is approaching $75,000. Cover: what the threshold means, that they must register within 21 days of exceeding it, what changes when they register (charging 10% GST on sales, claiming input tax credits on purchases, lodging BAS quarterly), and one common misconception — that registering for GST means they earn less (in fact the GST they collect is not their income). Under 250 words. Reassuring tone. I will add the specific projected figures and timeline separately.

2.5 Plain-English BAS lodgement summary (post-lodge client email)

After you lodge, most clients want to know what just happened. This template generates the narrative wrapper — you paste in the actual figures.

Write a post-lodgement summary email template for an accountant to send to a small business client after their quarterly BAS has been lodged. The email should explain in plain English: that the BAS has been lodged with the ATO, what the three main figures mean (GST payable/refundable, PAYG withholding, and net amount), what the client needs to do next (pay by [date] or expect refund by [date]), and one forward-looking note about the next quarter. Leave clear [PLACEHOLDER] markers for all specific dollar amounts and dates — I will fill these in. Professional but warm tone. Under 250 words.

3. Adapting prompts for Chinese-speaking clients

If your client is more comfortable in Mandarin or Cantonese, add one line to any prompt above:

Write the above in Simplified Chinese (普通话), keeping all Australian tax terms (BAS, GST, PAYG, ATO) in English the first time they appear, followed by a brief Chinese explanation in parentheses.

Or for a bilingual format that many Chinese-Australian clients actually prefer:

Format the above as a bilingual document: each paragraph in English first, then the same paragraph in Simplified Chinese immediately below it. Keep Australian tax terms in English in both versions.

A practical note on the Chinese version: many clients from mainland China are familiar with 增值税 (VAT/zēng zhí shuì) and will instinctively try to map GST onto that framework. The concepts are similar — both are consumption taxes on the value added at each stage — but there are real differences your client needs to know:

• Australian GST is reported quarterly via BAS, not monthly
• There is one federal authority (ATO), not a split state/national system
• Input tax credits are claimed on the same BAS form, not via separate invoices (fapiao)
• The rate is flat 10% — no tiered rates like China's 6%/9%/13%

You can instruct ChatGPT to include this comparison explicitly: add "Note that this client has a business background in China and is familiar with 增值税 — briefly explain how Australian GST is similar in concept but different in reporting frequency and administration" to any of the prompts above.

4. What you must NOT do with AI and BAS

This is the section most "AI for accountants" guides skip. Don't.

Hard rules for AI-assisted BAS communication:

• Never paste a client's TFN into ChatGPT. Tax File Numbers are sensitive information under the Privacy Act 1988 and the Tax File Number Guidelines. Sharing a TFN with an overseas AI processor is a potential breach regardless of intent. Strip all TFNs before pasting anything.
• Never paste actual GST amounts, PAYG figures, or real turnover. These figures identify your client's financial position. Use placeholder amounts in prompts — "a client with roughly $200k annual turnover" — and insert the real numbers yourself into the output before sending.
• Never let AI calculate the BAS figures. ChatGPT is a language model. It can make arithmetic errors. The BAS figures are your professional work product — calculated by you, reviewed by you, lodged by you. AI explains; you calculate.
• Review every AI-generated explanation before sending. Under the TPB Code of Professional Conduct, you are responsible for the accuracy of every communication you send to a client. An AI-generated explanation that contains an error about GST rates, due dates, or registration rules is your error, not ChatGPT's.
• Don't use AI for SMSF, complex trust structures, or crypto-related GST questions. These areas have fact-specific nuance and rapidly evolving ATO guidance. AI explanations in these areas carry meaningful risk of being materially wrong. Get specialist review before any client-facing communication.

5. The 10-minute client briefing kit

Here's the full workflow from lodgement to client sign-off. It takes under 10 minutes once you have the prompts set up.

1. Lodge the BAS as normal. Your software, your figures, your responsibility.
2. Open ChatGPT (Temporary Chat mode recommended). Paste prompt 2.5 — the post-lodgement summary template. Generate the output.
3. Add the real numbers. Replace every [PLACEHOLDER] with the client's actual figures: GST payable/refundable, PAYG withholding, net amount, due date, expected refund date.
4. Read it once as if you're the client. Check for jargon. Check the maths is coherent. Adjust one or two sentences to match your firm's voice.
5. Send. Client gets a professional, personalised summary the same day their BAS is lodged — before they've had a chance to worry about it.

The same kit works proactively: run prompt 2.1 for every new client at onboarding, before they ask the questions. Run prompt 2.4 when you see a sole trader approaching $75k. Run prompt 2.3 the week a client mentions they're about to hire someone.

That's client education at scale — without scaling your hours.

6. Don't miss fuel tax credits

Fuel Tax Credits are one of the most consistently under-claimed items on Australian BAS lodgements — especially for Chinese-Australian clients in construction, transport, landscaping, and trade services who weren't briefed on eligibility at registration.

If you have clients running vehicles or heavy machinery for business purposes, add this prompt to your new-client onboarding sequence:

Write a brief, plain-English explanation (150 words) for a [construction / landscaping / transport] business owner explaining what Fuel Tax Credits are, who is eligible, and that this credit can be claimed on their BAS. Note that rates change each February and August. Friendly, informative tone. I will verify the current rate with the ATO and add it before sending.

The ATO updates fuel tax credit rates twice a year (February and August). Always verify the current rate before including it in client communications — do not ask ChatGPT for the current rate, as it may be out of date.

7. Where to go next

If this guide gives you enough to build your own prompt library: start with the five templates above, save them in a shared notes file your team can access, and refine the tone over the first month. You'll probably cover 80% of your BAS explanation conversations.

If you want a full set of accounting-specific prompts — covering client onboarding, quarterly review emails, GST registration letters, PAYG instalment variations, and end-of-year client communications — already written and compliance-checked:

• Accounting AI Pack — A$49 (one-time, no subscription)
• Browse other Professional Services packs (legal, financial planning, migration)

If your practice has a specific workflow — multiple staff handling BAS, a large migrant client base, or bilingual communication needs across Mandarin and Cantonese — and you want a tailored setup:

• Custom AI Setup — Vince walks through your practice workflow and builds a prompt library specific to your client base and compliance requirements.