A New Tax System (Goods and Services Tax) Act 1999: A Plain-English Overview

Introduction

The A New Tax System (Goods and Services Tax) Act 1999 (the GST Act) is the cornerstone of Australia’s goods and services tax regime. Enacted on 1 July 2000, it replaced the former wholesale sales tax and introduced a broad-based consumption tax of 10% on most goods, services, and other supplies. For sole traders, small business operators, bookkeepers, and importers, understanding the GST Act is not optional—it is essential for compliance, cash flow management, and avoiding costly penalties.

This pillar article provides a plain-English overview of the GST Act, breaking down its key provisions into practical, actionable guidance. We cover who must register, what is taxable, how to claim input tax credits, how to lodge Business Activity Statements (BAS), the rules for importing goods, and special concessions for small businesses. Each section includes real-world examples, tables, and expert tips to help you apply the law correctly.

By the end of this guide, you will have a solid foundation to navigate GST compliance confidently. For specific calculations and transaction-level queries, use the GST Calculator Australia suite and searchable database.

What Is the A New Tax System (Goods and Services Tax) Act 1999?

The GST Act is the primary legislation that establishes the legal framework for the GST in Australia. It defines key concepts such as taxable supply, GST-free supply, input-taxed supply, and creditable acquisition. The Act also sets out the rules for registration, reporting, and payment of GST.

Purpose and Scope

The GST is a value-added tax (VAT) designed to tax private consumption. Businesses collect GST on their sales and remit it to the Australian Taxation Office (ATO), while claiming back the GST they pay on business inputs. The net effect is that the tax burden falls on the final consumer, not the business.

Key Definitions

• Taxable supply: A supply made for consideration in the course of an enterprise, connected with Australia, and not GST-free or input-taxed.
• GST-free supply: Supplies on which no GST is charged, but the supplier can still claim input tax credits (e.g., basic food, medical services, education).
• Input-taxed supply: Supplies on which no GST is charged, and the supplier cannot claim input tax credits (e.g., residential rent, financial supplies).
• Creditable acquisition: An acquisition of goods or services that is used in a creditable purpose (i.e., to make taxable supplies).

Expert Tip: The distinction between GST-free and input-taxed supplies is critical. A common mistake is assuming all non-taxable supplies are GST-free. Always check the specific category under the Act.

GST Registration – Who Must Register?

Registration is mandatory for businesses whose GST turnover (current or projected) exceeds the $75,000 threshold ($150,000 for non-profit organisations). Taxi and rideshare drivers must register regardless of turnover.

Voluntary Registration

Businesses below the threshold can voluntarily register. This allows them to claim input tax credits, which can be beneficial if they have high business expenses. However, they must then charge GST on their supplies and lodge BAS regularly.

Group Registration

Related entities can form a GST group to simplify reporting. One member lodges a single BAS for the group, reducing administrative burden.

Cancellation of Registration

If turnover falls below the threshold and the business no longer meets the registration requirements, it can apply to cancel registration. The ATO may also cancel registration if the business ceases to carry on an enterprise.

Warning: If you fail to register when required, you may be liable for GST on all supplies from the date you should have registered, plus penalties and interest.

Taxable Supplies and GST-Free Supplies

Understanding what is taxable and what is not is fundamental to correct GST treatment.

Taxable Supplies

A supply is taxable if it is made for consideration, in the course of an enterprise, connected with Australia, and not GST-free or input-taxed. The GST rate is 10% of the value of the supply. Examples: sale of goods, professional services, restaurant meals, new residential property.

GST-Free Supplies

These supplies are not subject to GST, but the supplier can claim input tax credits. Common categories include:

• Basic food (e.g., milk, bread, fruit, vegetables, meat, eggs)
• Medical and health services (e.g., doctor visits, hospital treatment)
• Education courses and materials
• Childcare services
• Exports of goods from Australia
• Water, sewerage, and drainage services

Input-Taxed Supplies

These supplies are also GST-free to the customer, but the supplier cannot claim input tax credits. Examples:

• Residential rent (not commercial rent)
• Financial supplies (e.g., loans, bank fees, insurance)
• Sale of residential premises (existing homes)
• Precious metals (gold, silver bullion)

Expert Tip: Mixed supplies (e.g., a restaurant meal that includes both food and alcohol) may have different GST treatments. You must apportion the supply correctly.

Input Tax Credits (ITCs)

Input tax credits allow businesses to recover the GST they pay on purchases used in their enterprise. This is the mechanism that ensures GST is only borne by the final consumer.

Entitlement to ITCs

You can claim an ITC if you make a creditable acquisition: you acquire goods or services for a creditable purpose (i.e., to make taxable supplies), you provide consideration, and you are registered for GST. The acquisition must be connected with your enterprise.

Partial ITCs

If you use an acquisition partly for business and partly for private purposes, you can only claim the business portion. For example, a mobile phone used 60% for work and 40% personal allows a 60% ITC.

Adjustments

If the use of an asset changes over time (e.g., a car used 100% for business initially but later used partly private), you may need to make an adjustment to the ITC claimed. The GST Act provides for annual adjustments for assets costing more than $5,000 (excluding GST).

Warning: You cannot claim ITCs for acquisitions that relate to making input-taxed supplies (e.g., residential rental property expenses). This is a common trap for property investors.

GST Returns and Business Activity Statements (BAS)

Registered businesses must report and pay GST to the ATO via the Business Activity Statement (BAS). The BAS also reports other taxes like PAYG withholding and fuel tax credits.

Reporting Methods

• GST Full (quarterly or monthly): Report total sales, GST on sales, total purchases, and GST on purchases. Net GST is calculated.
• GST Instalment (quarterly): The ATO calculates an instalment amount based on your previous returns. You pay that amount and do a final adjustment at year-end.

Due Dates

Quarterly BAS: due 28 days after the end of the quarter (e.g., for July–September, due 28 October). Monthly BAS: due 21 days after the end of the month. Annual GST returns are due 28 February after the end of the financial year (for those on annual reporting).

Penalties for Late Lodgment

The ATO imposes penalties for late lodgment and late payment. The penalty is calculated as a percentage of the GST shortfall, plus interest. For small businesses, the ATO may offer payment plans.

Expert Tip: Use the GST Calculator Australia’s BAS estimator to project your net GST position before lodgment. This helps avoid surprises and manage cash flow.

GST on Imports

Importing goods into Australia triggers GST liability. The GST is collected by the Australian Border Force (ABF) at the time of importation, unless a deferred GST scheme applies.

How GST on Imports Works

GST is calculated on the customs value of the goods plus any duty, insurance, and freight (CIF). The rate is 10%. For example, if the customs value is $1,000, duty is $50, and freight/insurance is $100, the GST is 10% of $1,150 = $115.

Deferred GST Scheme

Registered businesses can use the Deferred GST Scheme (also known as the GST deferral or import GST deferral) to defer payment of GST on imports until the next BAS lodgment. This improves cash flow. To qualify, you must be registered for GST, have a good compliance history, and lodge your BAS on time.

Low Value Imported Goods

Since 1 July 2018, GST applies to low value imported goods (valued at $1,000 or less) sold to Australian consumers. Overseas vendors with an Australian turnover of $75,000 or more must register and charge GST at the point of sale.

Warning: If you import goods for resale, ensure you claim the import GST as an input tax credit on your BAS. Failure to do so means you lose the credit.

Special Rules for Small Business

The GST Act provides several concessions to reduce compliance costs for small businesses.

Cash vs Accrual Accounting

Small businesses with a GST turnover of less than $2 million can use cash accounting for GST. This means you account for GST when cash is received or paid, not when invoices are issued. This helps with cash flow management.

Annual GST Returns

Businesses with a GST turnover of less than $75,000 (or $150,000 for non-profits) that are voluntarily registered can choose to lodge an annual GST return instead of quarterly or monthly BAS. This reduces lodgment frequency.

Simplified Accounting Methods

Certain industries (e.g., food retailers, cleaning services) can use simplified methods to calculate GST on mixed supplies. For example, the food retailer simplified method allows a fixed percentage of sales to be treated as GST-free.

Fuel Tax Credits

Small businesses that use fuel in machinery, vehicles, or equipment may be eligible for fuel tax credits. These are claimed on the BAS and can offset GST payable.

Expert Tip: If you are a sole trader with low turnover, consider voluntary registration only if your business expenses (and thus ITCs) are significant. Use the GST Calculator Australia’s registration decision tool to compare scenarios.

GST Calculator & Tools

The GST Calculator Australia suite provides a range of free tools to help you manage GST compliance efficiently.

How to Use the GST Calculator

1. Select the calculation type: Add GST (to find total including GST) or Remove GST (to find GST-exclusive amount).
2. Enter the amount in the input field (e.g., $100).
3. Choose the GST rate (default 10% for Australia).
4. Click Calculate to see the result instantly.

Sample Calculation Table

Beyond the basic calculator, the site offers a BAS estimator to project your net GST position, a registration decision tool, and a searchable database of how GST applies to thousands of specific goods and services. Use the database to check the GST treatment of your products before you invoice.

Common GST Mistakes to Avoid

Even experienced businesses make errors. Here are the most frequent mistakes and how to prevent them.

• Mistake 1: Claiming ITCs on input-taxed supplies – For example, claiming GST on expenses for a residential rental property. Prevention: Always check if the supply you are making is input-taxed. If so, no ITCs are available.
• Mistake 2: Not registering when turnover exceeds the threshold – This can result in backdated GST liability and penalties. Prevention: Monitor your GST turnover monthly. If it exceeds $75,000, register immediately.
• Mistake 3: Incorrectly treating GST-free supplies as taxable – Charging GST on basic food or medical services is illegal. Prevention: Use the ATO’s GST-free food list or the GST Calculator Australia database.
• Mistake 4: Failing to lodge BAS on time – Late lodgment attracts penalties and interest. Prevention: Set calendar reminders and consider using a bookkeeper or accounting software that auto-fills BAS.
• Mistake 5: Not claiming import GST as an ITC – If you import goods for resale, you can claim the GST paid at customs as an ITC. Prevention: Keep all import documentation and include the import GST in your BAS purchases.
• Mistake 6: Mixing personal and business expenses without apportionment – Claiming full ITCs on mixed-use assets. Prevention: Keep a logbook for vehicles and apportion expenses based on business use percentage.

Expert Tip: The ATO’s GST audit program targets common errors. Use the GST Calculator Australia’s compliance checklist to review your processes annually.

Conclusion

The A New Tax System (Goods and Services Tax) Act 1999 is a complex but navigable piece of legislation. By understanding the core concepts—registration, taxable supplies, input tax credits, BAS lodgment, import GST, and small business concessions—you can manage your GST obligations with confidence. Remember that the GST is a tax on consumption, not on business; your role is to collect and remit it correctly.

For day-to-day calculations and specific transaction queries, rely on the GST Calculator Australia suite. Our searchable database covers thousands of goods and services, and our tools help you estimate BAS amounts, decide on registration, and avoid common pitfalls. Bookmark this guide and revisit it as your business grows.

Always consult a registered tax agent for advice tailored to your specific circumstances. The information in this article is general in nature and does not constitute professional tax advice.