Goods and services tax, often known as GST, is a broad-based tax of 10% on most goods, services and other items sold or consumed in Australia. GST applies to most Australian businesses and it's highly likely that your business will be affected by the tax. If your business is registered for GST, you'll have to collect some extra money (one-eleventh of the sale price) from your customers and pay it to the Australian Taxation Office (ATO) when it is due.