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Common GST-free supplies include:

• Basic food — bread, milk, fruit, vegetables, meat, eggs (prepared and restaurant food remains taxable)
• Most healthcare — doctor, dentist, hospital services; many medicines
• Education — pre-school, primary, secondary, university courses, and approved training
• Childcare — registered childcare services
• Exports — goods and services exported from Australia within 60 days
• Religious services and certain non-profit fundraising

For GST-free supplies, no GST is charged but the supplier can still claim GST credits on related business purchases.

Input-taxed supplies are sales where no GST is charged to the customer, but the supplier cannot claim GST credits on related expenses. The two main categories are:

• Residential rent — rent paid by tenants for residential premises
• Financial supplies — bank account fees, loans, life insurance, share trading, superannuation

This treatment differs from GST-free supplies, where suppliers can still claim credits on inputs.

Both result in no GST being charged to the customer, but they have different consequences for the seller:

• GST-free (e.g. basic food, healthcare, exports): no GST on the sale, but the seller can claim GST credits on business expenses related to the sale.
• Input-taxed (e.g. residential rent, financial supplies): no GST on the sale, and the seller cannot claim GST credits on related expenses.

Input-taxed treatment effectively absorbs GST into the cost of the supply rather than passing it through the system.

Treatment depends on the type of property and transaction:

• New residential premises sold by a developer: GST applies at 10%, often calculated under the margin scheme
• Established residential property sold between private parties: GST does not apply
• Residential rent: input-taxed (no GST charged, no credits claimable on expenses)
• Commercial property sales and rent: GST applies at 10% if the seller or landlord is GST-registered

The ATO assigns a lodgement cycle based on annual GST turnover:

• Monthly — mandatory for businesses with annual GST turnover of AUD 20 million or more (optional for smaller businesses)
• Quarterly — standard cycle for businesses below AUD 20 million turnover
• Annually — available for voluntarily registered businesses with turnover under AUD 75,000 (AUD 150,000 for non-profits)

Self-lodged quarterly BAS due dates for the 2026–27 financial year:

• Q1 (Jul – Sep 2026): due 28 October 2026
• Q2 (Oct – Dec 2026): due 28 February 2027 (includes built-in one-month holiday extension)
• Q3 (Jan – Mar 2027): due 28 April 2027
• Q4 (Apr – Jun 2027): due 28 July 2027

Lodging through a registered tax or BAS agent typically extends Q1, Q3 and Q4 due dates by approximately four weeks. No agent extension applies to Q2.

The ATO applies a Failure to Lodge (FTL) penalty calculated in penalty units. From 7 November 2024, one penalty unit is AUD 330.

• Small entities (turnover under AUD 1 million): 1 penalty unit per 28-day period, capped at 5 units (max AUD 1,650)
• Medium entities (AUD 1m – 20m): 2 penalty units per period, max 10 units
• Large entities (AUD 20m+): 5 penalty units per period, max 25 units

General Interest Charge also accrues daily on any unpaid amount and is no longer tax-deductible from 1 July 2025.

Yes, businesses below the AUD 20 million turnover threshold can elect to report monthly instead of quarterly — common for businesses regularly in a GST refund position to receive faster refunds.

Changes to the reporting cycle can be requested through Online services for business or via a registered tax or BAS agent. The new cycle generally takes effect from the start of the next quarter or financial year, depending on when the change is requested. The ATO can also direct a business onto monthly reporting in cases of repeated non-compliance.

Yes. If registered for GST, a BAS must be lodged for every reporting period — even when there were no sales or purchases. This is known as a nil BAS.

Failing to lodge a nil BAS triggers automatic FTL penalties just like a late BAS with figures. Nil BAS lodgements can be completed quickly through Online services for business or by phone.

If registered for GST and making a taxable sale of AUD 82.50 or more (including GST), a tax invoice must be provided to the customer if requested. The ATO allows up to 28 days to issue the invoice after the request.

For sales under AUD 82.50, a tax invoice is not required, but a receipt or other written record should be retained.

For taxable sales under AUD 1,000, a tax invoice must show:

• The words "Tax invoice"
• Seller's identity and ABN
• Date of issue
• Brief description of items sold (with quantity if applicable)
• GST amount payable, or a statement that "Total price includes GST"
• The extent to which each sale is taxable

Tax invoices for sales of AUD 1,000 or more must additionally include the buyer's identity or ABN.

GST credits (input tax credits) can be claimed if all of the following apply:

• The business is registered for GST
• The purchase is for business use, not personal
• GST was included in the price paid
• A valid tax invoice is held for purchases over AUD 82.50 (GST-inclusive)
• The credit is claimed within the four-year time limit

Credits are claimed through the BAS — the difference between GST collected on sales and GST paid on purchases is the net amount remitted to (or refunded by) the ATO.

An invoice missing any of the mandatory elements is non-compliant, and the ATO can deny the related GST credit claim during an audit. The most common errors are:

• Supplier's ABN not shown
• GST amount not shown separately or no "includes GST" statement
• Buyer's identity missing on sales of AUD 1,000 or more

If a non-compliant invoice is identified, the supplier can typically reissue a corrected version. Records should be kept for at least 5 years to support credit claims under audit.