What is GST in Australia?

Goods and Services Tax (GST) is a 10% tax applied to most goods and services sold in Australia. Businesses registered for GST must include the tax in their prices and report the GST collected to the Australian Taxation Office (ATO) through their Business Activity Statement (BAS). Consumers usually see GST included in the final price they pay.

How do you calculate GST in Australia?

GST in Australia is calculated at a standard rate of 10%. To add GST to a price: multiply the original price by 1.10. To remove GST from a GST-inclusive price: divide the total price by 1.10. The GST portion itself can also be calculated by dividing the GST-inclusive price by 11.

How do I add GST to a price?

To add GST to a price, multiply the original amount by 1.10. Example: if a product costs $100 excluding GST: $100 × 1.10 = $110 including GST Your GST calculator can instantly add GST to any amount without manual calculations.

How do I remove GST from a price?

To remove GST from a GST-inclusive price, divide the total amount by 1.10. Example: if an invoice total is $110 including GST: $110 ÷ 1.10 = $100 excluding GST This helps businesses determine the original price before GST was applied.

How do I calculate the GST amount only?

To calculate just the GST component of a GST-inclusive price, divide the total price by 11. Example: $110 ÷ 11 = $10 GST This formula is commonly used when preparing invoices or reconciling GST during BAS reporting.

What items are GST-free in Australia?

Some goods and services in Australia are GST-free, meaning GST is not charged. Common examples include basic food items, most medical and healthcare services, educational courses, and exports of goods and services. Businesses can still claim GST credits on expenses related to GST-free sales.

When do businesses need to register for GST?

Businesses must register for GST if their annual turnover reaches $75,000 or more. Non-profit organisations must register once their turnover reaches $150,000. Once registered, businesses must charge GST on taxable sales, lodge Business Activity Statements (BAS), and report GST collected and GST credits to the ATO.

What is a BAS and how is GST reported?

A Business Activity Statement (BAS) is the form businesses use to report GST to the Australian Taxation Office. Businesses usually lodge BAS monthly or quarterly, depending on their reporting cycle. The BAS calculates the difference between GST collected on sales and GST credits claimed on business purchases. The result determines whether the business pays GST to the ATO or receives a refund.

GST Calculator Australia (Add or Remove 10% GST)

Instantly add or remove 10% GST. Calculate invoices, estimate your BAS, and check registration thresholds — all free, based on current ATO rates.

Based on official ATO rates

Updated for 2025–26

Covers all GST scenarios

10%

GST rate

$75K turnover

Registration threshold

28 Oct 2026

Next BAS due

Understanding the system

How GST Works in Australia

GST isn't just "add 10%". Whether you owe the ATO or get a refund depends on what you sell, what you buy, and how you classify each transaction. Here's the detail that actually matters.

Same $1,000.00 Item, Three Different Outcomes

Every sale falls into one of three GST categories. The category determines what your customer pays and whether you can claim credits on your costs.

Taxable

$1,100.00

Customer pays (inc-GST)

Your price$1,000.00

GST collected$100.00

Input tax creditsYes

Most goods and services. You charge GST, remit it via BAS, and claim credits on business costs.

GST-Free

$1,000.00

Customer pays

Your price$1,000.00

GST collected$0.00

Input tax creditsYes

Basic food, medical services, education, exports. No GST charged but you can still claim credits on related purchases.

Input Taxed

$1,000.00

Customer pays

Your price$1,000.00

GST collected$0.00

Input tax creditsNo

Residential rent, financial services, life insurance. No GST charged and you cannot claim credits on related costs either.

The critical difference: GST-free and input-taxed both mean your customer pays no GST. But with GST-free supplies, you can still claim credits on your business costs. With input-taxed supplies, you absorb the GST on your expenses — it becomes part of your cost base. For a business spending $65,000.00/quarter on taxable purchases, that's $6,500.00 in unrecoverable GST per quarter if your sales are input-taxed.

Not sure how to classify a sale? Use the GST Classification Tool or check the GST-free items guide.

How a Mixed Invoice Actually Works

Most businesses have a mix of taxable, GST-free, and input-taxed sales. GST only applies to the taxable portion.

Line item	Amount	Status	GST
Consulting services	$5,000.00	Taxable	$500.00
Training materials	$2,000.00	Taxable	$200.00
Export consulting	$3,000.00	GST-free	—
Financial advisory	$1,500.00	Input taxed	—
Total	$11,500.00		$700.00
Invoice total (inc-GST)			$12,200.00

Of the $11,500.00 invoice, only $7,000.00 is subject to GST. The $3,000.00 in exports and $1,500.00 in financial advisory are excluded — the customer doesn't pay GST on those lines and they don't appear on your BAS as GST collected.

Build your own mixed invoice with the Invoice GST Calculator.

Your BAS in 30 Seconds

A typical quarter for a business with $120,000.00 in taxable sales, $30,000.00 in GST-free sales, and $65,000.00 in business purchases.

GST Collected (1A)

$12,000.00

10% of $120,000.00 taxable sales

GST Credits (1B)

$6,500.00

10% of $65,000.00 purchases

You Owe ATO

$5,500.00

$12,000.00 collected − $6,500.00 credits

= $1,833.00/month to set aside

The $30,000.00 in GST-free sales doesn't affect your GST calculation at all — no GST is collected and it doesn't appear in labels 1A or 1B. But you can still claim GST credits on purchases related to making those GST-free sales.

Estimate your own BAS with the BAS Estimator or read the BAS lodgement guide.

Why 10% of $110 Isn't the GST

The most common GST calculation mistake — and it gets more expensive as the numbers get bigger.

Wrong way

$11,000.00 × 10% = $1,100.00

Taking 10% of the GST-inclusive amount gives you more than the actual GST. You'd over-report by $100.00 per $11,000.00.

Right way

$11,000.00 ÷ 11 = $1,000.00

GST is 1/11th of the inclusive price because it's 10% of 110% (the original price plus GST). Dividing by 11 gives the exact GST component every time.

Inc-GST Price	Correct GST (÷ 11)	Wrong (× 10%)	Over-report by
$110.00	$10.00	$11.00	+$1.00
$550.00	$50.00	$55.00	+$5.00
$1,100.00	$100.00	$110.00	+$10.00
$5,500.00	$500.00	$550.00	+$50.00
$11,000.00	$1,000.00	$1,100.00	+$100.00
$55,000.00	$5,000.00	$5,500.00	+$500.00

At $55,000.00, the difference is $500.00 per transaction. Over a year of invoices, this adds up to a material BAS error that can trigger an ATO review.

What Most Businesses Don't Realise

Four facts that can save you money — or cost you if you don't know them.

Registration cliff

$75,000.00

At $74,999.00 annual turnover — zero GST obligations. At $75,001.00 — full compliance: register, charge GST, lodge BAS, keep tax invoices. Non-profits get a $150,000.00 threshold. Taxi and rideshare drivers must register regardless of turnover.

Check your registration status

Tax invoice rules

$82.50 threshold

You need a valid tax invoice to claim any GST credit over $82.50 (inc-GST). Below that, a receipt or bank statement is enough. Above it, the invoice must show the supplier's ABN, the word "tax invoice", the GST amount, and date of issue. Missing one of these? The ATO can deny the entire credit.

Input tax credits guide

Cash flow timing

$1,833.00/month

On $120,000.00/quarter in taxable sales, you should set aside $1,833.00 monthly for your BAS payment. Most businesses that get into GST trouble don't have a tax problem — they have a cash flow problem. They spend the GST they've collected before the BAS is due.

Estimate your BAS

Under the threshold?

Sometimes register anyway

If your customers are businesses (B2B), they may prefer GST-registered suppliers because they can claim your GST as a credit. And if you have significant startup costs or capital purchases, voluntary registration lets you claim back the GST on those expenses — even if you're below $75,000.00.

GST for small business guide

How Much GST Will You Actually Owe?

Net GST payable at common revenue levels, assuming 55% of revenue goes to GST-inclusive business expenses (typical for a small service business). Your actual amount depends on your expense ratio.

$100K

$4,500.00/year

$375.00/mo

$250K

$11,250.00/year

$938.00/mo

$500K

$22,500.00/year

$1,875.00/mo

$1M

$45,000.00/year

$3,750.00/mo

$2M

$90,000.00/year

$7,500.00/mo

Revenue shown is ex-GST. Assumes all sales are taxable and 55% of revenue is spent on GST-inclusive business expenses. Businesses with higher expense ratios (e.g. retail, manufacturing) will owe less. Businesses with lower expenses (e.g. consulting) will owe more.

Why GST Matters More Than You Think

GST is Australia's third-largest source of tax revenue — collecting over $73 billion in 2023-24. Unlike income tax, it's a consumption tax: the burden falls on the end consumer, and businesses are the collection mechanism. Getting it right isn't just about compliance — it's about pricing accurately, managing cash flow, and maximising the credits you're entitled to.

The calculator above handles the maths. For deeper questions — classification, BAS lodgement, industry-specific rules — explore the GST guides or use the specialised calculators.

GST Quick Reference — Common Amounts

Quick lookup for GST on common price points. The GST component is always 1/11th of the GST-inclusive price.

$100.00 ex-GST

GST: $10.00
Inc-GST: $110.00

$250.00 ex-GST

GST: $25.00
Inc-GST: $275.00

$500.00 ex-GST

GST: $50.00
Inc-GST: $550.00

$1,000.00 ex-GST

GST: $100.00
Inc-GST: $1,100.00

$2,500.00 ex-GST

GST: $250.00
Inc-GST: $2,750.00

$10,000.00 ex-GST

GST: $1,000.00
Inc-GST: $11,000.00

Based on the standard 10% GST rate. Use the calculator above for custom amounts.

Removing GST — Common Inc-GST Prices

$110.00 inc-GST

GST: $10.00
Ex-GST: $100.00

$275.00 inc-GST

GST: $25.00
Ex-GST: $250.00

$550.00 inc-GST

GST: $50.00
Ex-GST: $500.00

$1,100.00 inc-GST

GST: $100.00
Ex-GST: $1,000.00

$2,750.00 inc-GST

GST: $250.00
Ex-GST: $2,500.00

$11,000.00 inc-GST

GST: $1,000.00
Ex-GST: $10,000.00

Learn more

GST Guides

In-depth guides to help you understand GST and make informed business decisions.

How to Calculate GST in Australia

Step-by-step guide to calculating GST — adding 10%, removing GST from a total, and handling GST on invoices and BAS statements.

GST-Free Items in Australia

Complete guide to goods and services exempt from GST, including fresh food, health, education, and exports.

GST Registration Threshold in Australia

When you need to register for GST, the $75,000 threshold, voluntary registration benefits, and how to register with the ATO.

GST for Small Business: Complete Beginner's Guide

Everything Australian small business owners need to know about GST — registration, charging GST, BAS lodgement, input tax credits, record-keeping, and common mistakes.

GST for Freelancers & Sole Traders

Practical guide to GST for Australian freelancers — registration, invoicing, claiming credits on expenses, overseas clients, home office, and common mistakes.

Input Tax Credits: What You Can (and Can't) Claim

Complete guide to GST input tax credits — which purchases qualify, blocked credits to avoid, tax invoice rules, apportionment for mixed-use, the car limit, and the 4-year time limit.

GST on Property: Residential, Commercial & Margin Scheme

How GST applies to property sales in Australia — new residential premises, commercial property, the margin scheme, going concern exemptions, GST withholding at settlement, and when subdivisions trigger GST.

BAS Lodgement Guide: How to Prepare & Submit

Step-by-step guide to preparing, lodging, and paying your Business Activity Statement — with 2025-26 due dates, Simpler BAS labels, lodgement methods, payment options, and penalty rates.

View all guides →