Estimating how much heating oil you use may not be a simple calculation, as many variables are taken into account – size of your house, its actual heated area, quality of insulation, condition of your heating equipment, room layout, time spent at home, outside temperature and of course – one’s own feeling of “warm”  which can further depend on lifestyle and health condition.

Approximate Daily Heating Oil Usage vs Temperature F


For example, if the outdoor temperature is 15F you can expect to use about 7.8 gallons of heating oil in 24 hours; if it’s 20F outside, you can expect to use about 7 gallons in 24 hours.

Find an average monthly temperature there and multiply it with number of days in that month to get your monthly heating oil consumption in gallons. Note that this chart relies upon a mean sized home. For larger homes this curve goes up, for smaller ones it goes down. But knowing that many things influence  your heating oil usage, you might need to find it out from experience in a couple of months at the heating season’s beginning. Later you may use the data above to forecast trends in consumption with respect to all variables mentioned before.

This task is actually pretty straightforward if your heating oil tank features an oil gauge – thanks to it you can know how fast your heating oil is being consumed in various conditions and scenarios. You will, however, also need to check whether oil gauge is properly adjusted and is the floating device which delivers the data maybe stuck inside tank. Inaccurate gauge measurements may pose a substantial risk, not only from running out of fuel but also from possible damage to your heating system.

If your tank doesn’t feature an oil gauge it’s first required to know the volume of your oil tank, and if you don’t it’s needed to measure its dimensions and make a simple calculation. Now when you know the number of gallons that can fit in your tank you should do frequent measurements with a dipstick or temperature strip.

Automatic delivery can be a good choice. You don’t need to worry about how much oil you have and whether it will arrive during severe weather events. However, in order to get the best from a service like this it is required to know how much oil you use on average.


Below is a chart showing historic monthly temperature data for Long Island NY. This chart is from and can help you estimate your average annual consumption. You can also use previous season data and long time forecasts from which are available for most locales in detail.


Average temperature on Long Island (F)

To properly apply this data for heating oil usage calculation you need to know the number of gallons consumed daily in relation to average daily temperature.  This relation is shown in the following chart (average usage, your data may vary):

Another useful fact to know is what your K-factor is. K-factor is a number showing how fast a household uses fuel. Think of a k-factor as gallons per degree day, similar to miles per gallon. The K-factor is calculated by dividing the number of degree days between fuel oil deliveries by the gallons of fuel used between those deliveries. Use the K-factor calculator to estimate your k-factor.

You will need to refill your tank once the oil level in it drops to 1/4 of its volume. Never let the entire oil burn out as it can cause damage to the burner or furnace.

All automatic and online heating oil delivery services consider this and if they get correct data from you related to your heating oil usage you will always have orderly deliveries which would save you much time, energy and money.