FuelWatch is empowered to monitor and report on WA wholesale and retail fuel prices under the Petroleum Products Pricing Act 1983 . The Act gives the Government authority to enforce price transparency. The Act originally applied to a range of products, but it was amended in 1983 to apply solely to fuel products.
The Act enables the Government to make Regulations and authorises the ‘Prices Commissioner’ to publish Orders. These Regulations and Orders then direct the way the Act is enforced.
In 2000/2001 the Act was substantially amended following the Select Committee on Pricing of Petroleum Products report, 'Getting a Fair Deal for Western Australian Motorists’. The report was produced in response to WA motorists' frustration at intra-day price fluctuations and the significant difference between city and country fuel prices.
The Act supports the following key tools which help FuelWatch to achieve it goal of price transparency.
The Terminal Gate Price (TGP) provides transparency of petrol and diesel wholesale prices in WA. Suppliers selling fuel (to retailers and distributors) from a terminal are able to set their own price as long as it complies with a specific formula called the Terminal Gate Price (TGP). The TGP formula is based on an Import Parity Pricing model, which effectively ensures the price of fuel in Australia is competitive with the price that could be earned if the wholesale supplier exported the fuel.
The TGP calculation considers:
Below is an example of the TGP components that influence the price of fuel, along with excise, GST and retailer margin. Some of the percentages represented in the model below can vary on a day-to-day basis according to global supplies and demands.

The TGP system increases the transparency in the wholesale fuel market - providing eligible retailers and distributors with comparative prices (between oil companies) allowing them to make informed decisions about their wholesale fuel purchases.
The TGP is fixed for a minimum of 24 hours and suppliers will not be able to make sales to eligible retailers, distributors or other resellers above this price. Generally, TGP prices only change about twice a week – giving potential purchasers sufficient time in which to arrange a purchase at a particular price.
Retailers must:
The Prices Commissioner can compel people to answer questions, take samples, provide documents, seize documents as well as request other information relating to fuel pricing. These powers assist the Prices Commissioner to monitor developments in the wholesale and retail sectors of the industry that may affect fuel pricing and price transparency.
The 50/50 rule gives retailers greater flexibility in their purchasing power by giving retailers the right to purchase up to 50 per cent of their fuel supplies from a supplier other than their primary contract supplier. In exchange, retailers have certain obligations to properly label the fuel and store it separately.
Under the Petroleum Products Pricing Regulations 2000, non-metropolitan retailers within the FuelWatch boundaries are required to display their fuel prices on clearly legible roadside price boards. The rule was introduced to further encourage price transparency and competition in the regional areas. The increased competition has also helped to reduce the fuel price differential between metropolitan area and many regional towns.
Prices for at least three fuel types must be displayed, one of which must be unleaded petrol and or LPG autogas (if sold at that location). If the retailer sells fewer than three fuel types, they must display the prices for all the fuels sold.