How to Calculate Your Gas Bill

Look at an old bill, or call the gas company, and find out the current rate and what kind of taxes, surcharges or other fees are added to the bill. These could be straight charges, or may be a percent of usage.

Look on your current bill and find the current usage. You can also estimate what you think your usage will be, based on past experience. This will give you the opportunity to estimate your bill before it arrives. This might be in units of cubic feet, therms or British thermal units. Because the rate will most likely be in the same units, you do not need to worry about conversions.

Multiply your current or expected consumption by the rate. In the example, if you are charged 35 cents per unit, and you consumed 30 units, you are charged $10.50 for the gas itself.

Add any straight fees, such as billing fees or customer charges. As an example, if the gas company charges $5 to bill you, your total is now $15.50.

Divide any percent charges, such as taxes, by 100 to convert it into decimal format, and then multiply that by the charge for gas. Add this result to the total. In the example, if you are charged a 3 percent state tax and an 8 percent municipal tax, you are charged an additional 32 cents for state taxes and 84 cents for city tax. Therefore, your total bill will be $16.66.