I just got our first oil delivery since last May and I calculated that we used 31.6 gallons of heating oil per month over that time. This would be almost entirely for hot water only, as we've barely run the furnace for heat this fall (new pellet stove!).
I'm curious if 31 gal/mo is a lot of oil for a family of 4 (two small children)? About right? Anyone care to share?
Really depends on how many gallons of water you are using, and the temp that you have the water heater set at. Also, if you do a lot of dishes in the dishwasher, long hot showers, use warm or hot water to do clothes. You have to factor in how you are using, and what you are using, to determine.
Your company that delivers oil, should be able to figure the average for home owners in your area, to best determine where your home stands.