The average American family will spend $1,000 on heat this season, according to U.S. Energy Information Administration projections. Take a bite out of that with the following measures. (The savings estimates from the Edison Electrical Institute refer to your annual energy bill; results will depend on many factors, such as region.)

Check Filters and Vents

To keep the heat flowing freely and protect the furnace from being overworked, check the filter monthly and replace it every three months (see Furnace Filter Replacement Reminder). Be sure furniture, drapes, and rugs don’t block air vents, and keep grilles dusted to discourage lint and dirt buildup.
Frequency: Check filters and vents each month; replace filters every three months.
Potential Savings: 10 to 15 percent.

Lower the Water Temperature

Instead of keeping the water heater set at the usual 160 degrees, lower it to 120. Does this mean you won’t get a hot shower in the morning? No. You’ll just start with water less scalding than usual, says Doug Anderson of Energy Star, part of the U.S. Department of Energy. Water-heater thermostats can be inaccurate, he adds; check yours by sticking a cooking thermometer under a running tap, then adjust the thermostat as needed.
Frequency: Once per winter.
Potential Savings: 10 to 15 percent.

Shut the Damper

When not in use, a fireplace can be a major heat waster. Since warm air rises, yours can rush right up — and out — the chimney. Always close the damper (the metal plate that opens and seals the chimney stack) once the fire is safely out. Shutting glass fireplace doors does the same job.
Frequency: Daily; double-check at night.
Potential Savings: 2 to 18 percent.

Close Off Unused Rooms

There’s no reason the whole house needs to be warm all the time. Close doors to, and heating vents in, any room you’re not using, especially upstairs (the farther from the basement the heat has to travel, the harder the heater has to work). This way, the heater can more efficiently keep the rooms you are occupying nice and toasty.
Frequency: Daily.
Potential Savings: Up to 3 percent.

Use Ceiling Fans

The ceiling fan that cools you all summer can warm you in winter. Using it on the reverse setting (most fans have one), set on low, pushes warm air that has risen to the ceiling back to the ground. This lets you adjust the thermostat down a few degrees without suffering for it.
Frequency: Daily.
Potential Savings: Up to 3 percent if you lower the thermostat.