What do I need to prepare a BAS?

Reconciled bank and card accounts, sales and purchases coded with the right GST codes, payroll that agrees with Single Touch Payroll, the client’s PAYG instalment details from the ATO, and the client’s approval of the figures before lodgment. Close the month first with the month-end close checklist.

What are the most common BAS mistakes?

GST claimed on purchases that had none (wages, bank fees, some insurance), private use not adjusted, unreconciled accounts, wages that do not match STP, and import GST taken from the supplier invoice instead of the ATO statement. Payday super and payroll compliance risks covers the payroll side.

A reporting method for eligible small businesses that reports only G1, 1A and 1B for GST. The checklist notes the labels you can skip when it applies. Check the ATO’s current eligibility rules each year.

Does the client need to approve the BAS?

Yes. The client declares that the information is true and correct. Send them the figures and keep their written approval on file before you lodge.

Free template

BAS preparation checklist for bookkeepers and accountants

A BAS goes wrong in the same few places: a bank account nobody reconciled, a purchase coded with GST that had none, wages that do not match Single Touch Payroll, or a client who approved a figure they never saw. This checklist walks one client’s BAS from set-up to lodgment, label by label, so the review finds nothing. Australia only, as at November 2026.

Updated 10 November 2026 · Editable Word document (.docx) · Free with a firm profile

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How to use it

How to use this template

One copy per client, per period

Tick, initial and note as you go. The reviewer signs the last section. The accounting firm compliance deadlines calendar helps you plan the periods.
Check the set-up once a year

Section 1 changes rarely: GST basis, reporting cycle, instalment method and authorities. Confirm it at the first BAS of each financial year. BAS agent and tax agent pathways explains what each registration covers.
Leave a note on anything unusual

A large or one-off item, a change from last period, or a question for the client. The reviewer reads the notes first.
Get the client’s approval in writing

The client declares the BAS is true and correct. Send them the figures and keep their approval before you lodge.

The template

[Firm name] BAS preparation checklist: [client code], [period]

Replace everything in [square brackets].

1. Set-up (confirm at the first BAS of the year)

The client is linked to our registered BAS or tax agent number in Online services for agents, and the authority covers activity statements.
GST registration, accounting basis (cash or accruals) and reporting cycle (monthly, quarterly or annual) match ATO records: [basis, cycle].
Whether the client uses Simpler BAS reporting, and whether it still qualifies.
PAYG instalment method (amount or rate) and the current instalment from the ATO: [method].
Due date for this period, including any lodgment program concession: [date].

2. Reconciliations

Every bank, credit card and loan account reconciled to the statement at period end.
Clearing, suspense and undeposited funds accounts cleared or explained.
Receivables and payables aged lists reviewed; duplicates and old items followed up.
Payroll in the ledger agrees with Single Touch Payroll for the period.
GST control account reconciles to the previous BAS and payments made.

3. GST on sales and purchases

Label	What to check	Done
G1 Total sales	Includes GST-free and export sales; agrees with the income accounts on the chosen basis.	Blank
G2, G3 Exports and other GST-free sales	Coded correctly (not reported where Simpler BAS applies).	Blank
1A GST on sales	Matches the tax codes on sales; no GST on GST-free or input-taxed items.	Blank
G10, G11 Capital and other purchases	Capital purchases in G10 and other purchases in G11, following the ATO guidance on what counts as capital (not reported where Simpler BAS applies).	Blank
1B GST on purchases	A valid tax invoice is held where the ATO requires one; no GST claimed on wages, bank fees, insurance stamp duty, private or input-taxed items.	Blank

4. Adjustments

Private use of business purchases adjusted (motor vehicles, phones, home office).
Deferred GST on imports (7A) taken from the ATO statement, not the supplier invoice.
Bad debts written off and recovered adjusted for GST.
Fuel tax credits (7D) worked out at the rates for the period the fuel was acquired, where the client claims them.
Wine equalisation tax and luxury car tax, where they apply.

5. PAYG withholding and instalments

Label	What to check	Done
W1 Total salary and wages	Agrees with Single Touch Payroll gross payments for the period.	Blank
W2 Amounts withheld from wages	Agrees with STP tax withheld.	Blank
W4, W3 Other amounts withheld	No-ABN withholding and other withholding, where it applies.	Blank
T7 or T1 and T2 PAYG instalment	The ATO instalment amount, or income times the instalment rate. Any variation is documented and reasonable.	Blank

6. Review, approval and lodgment

Each label compared with the same period last year and the last period; movements explained in a note.
Reviewed by [name] on [date].
Figures sent to the client with the amount payable or refundable and the due date; written approval received on [date].
Lodged on [date]; receipt number [number] saved to the client file.
Payment reference and due date sent to the client, or the refund noted.
Next period’s due date and any open questions recorded in [practice management software].

Check the ATO’s current lodgment program, Simpler BAS rules and thresholds before relying on this checklist; they change. This template is a starting point, not legal advice. Your obligations depend on where you practise, your professional body and your clients; take advice on anything you are unsure of.

Common questions

Frequently asked questions

What do I need to prepare a BAS?: Reconciled bank and card accounts, sales and purchases coded with the right GST codes, payroll that agrees with Single Touch Payroll, the client’s PAYG instalment details from the ATO, and the client’s approval of the figures before lodgment. Close the month first with the month-end close checklist.
What are the most common BAS mistakes?: GST claimed on purchases that had none (wages, bank fees, some insurance), private use not adjusted, unreconciled accounts, wages that do not match STP, and import GST taken from the supplier invoice instead of the ATO statement. Payday super and payroll compliance risks covers the payroll side.
What is Simpler BAS?: A reporting method for eligible small businesses that reports only G1, 1A and 1B for GST. The checklist notes the labels you can skip when it applies. Check the ATO’s current eligibility rules each year.
Does the client need to approve the BAS?: Yes. The client declares that the information is true and correct. Send them the figures and keep their written approval on file before you lodge.

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