Fuel & Tanks
Heating Oil Runout Calculator
Estimate when your heating oil tank will run dry based on tank size, gauge reading, and the weather. Free calculator — no dipstick guessing, no hardware.
Frequently asked questions
How long will a 275-gallon tank of oil last?
A full 275-gallon tank holds about 240 usable gallons. In cold weather a typical home burns 4–7 gallons per day, so a full tank lasts roughly 4–8 weeks at peak winter; in milder weather it can stretch for months. Home size, insulation, and temperature drive the difference.
At what level should I order heating oil?
Order when your gauge reaches about ¼ tank — roughly 70 gallons on a 275-gallon tank. That buffer covers normal delivery lead times and a cold snap, and keeps the burner from drawing air and sludge off the bottom of the tank.
How much heating oil does a house use per day in winter?
A typical home uses 4–7 gallons of heating oil on a cold winter day, and less in milder weather. Usage tracks outdoor temperature closely (measured as heating degree-days), so an extended cold snap can sharply increase your daily burn.
What happens if you run out of heating oil?
The burner shuts down and you lose heat. Restarting usually requires bleeding air from the fuel line (and sometimes replacing a clogged filter or nozzle, since the tank’s sediment gets stirred up), which often means a service call. Ordering at ¼ tank avoids the whole situation.
How do I read a heating oil tank gauge?
Most tanks have a float gauge on top showing Full, ¾, ½, and ¼. If there’s no gauge, you can “stick” the tank with a clean dowel and compare the wetted depth to your tank’s chart. Float gauges can stick, so it’s worth confirming periodically.