Usage Rates are the price you pay for each unit of gas consumed for cooking or heating or running hot water units. A measure of gas is called a megajoule (MJ), and unit prices are displayed as cents per megajoule (c/MJ). Some gas offers use block tariffs. Block tariffs have different prices between one block (quantity) of gas and the next, often decreasing with volume. If you are household or business in the ACT, NSW, NT, QLD, SA, TAS, VIC or WA we’ve got you covered with gas retailer’s latest usage rates.