Home Kilowatt

Radiant Floor Heating Running Cost

Enter the heated floor area, the mat's watts per square foot and the hours it's on, and get the cost per month and for a 5-month winter.

Radiant floor heating tubing laid in loops on a subfloor.

Radiant floor heating

B11

Scenario A

Sets the electricity rate. Pick US average if you're not sure.

$/kWh

From EIA for US average. Use the rate on your bill if you know it.

Rate used: 18.4¢/kWh · US average · EIA reference 2025–26 (data as of 2026-09-26) ·

sq ft
W/sq ft
h

The thermostat cycles the mat; 0.5 = on half the time.

Estimated cost per month

$26.50/ month
Installed power
1,200 W
kWh per month
144
Cost per month
$26.50
Cost per winter (5 months)
$132.48

Estimate. Formula and sources are under “How it works”. Change any input; the result updates as you type.

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2026 note: The federal 25C and 25D tax credits ended for installations after Dec 31, 2025. Our numbers use 2026 rules. State rebates, HEAR/HOMES programs and utility programs may still apply.

Formula

How it works

  • Installed power (W) = heated area × watts per sq ft
  • kWh per month = watts ÷ 1,000 × hours per day × 30 × duty cycle
  • Cost per month = kWh per month × your rate
  • Cost per winter = cost per month × 5

An electric floor is resistance heat: every kWh becomes 3,412 BTU, no more. For a bathroom that is a small number. Heating a whole house this way costs the same per unit of heat as baseboard or an electric furnace.

Radiant floor heating tubing laid in loops on a subfloor.

Sources: manufacturer data for electric floor-heating mats (about 12 W per sq ft; floor thermostats cycle about 50%); electricity rate from EIA Electric Power Monthly table 5.6.A.

Worked example

A worked example

A 60 sq ft heated bathroom floor at 15 W per sq ft has 900 W installed. On 6 hours a day and heating half that time, it uses 81 kWh a month. At New York's reference rate of 25.0¢/kWh, that's $20.25 a month, or $101.25 over a 5-month winter.

Open this example in the calculator

Reference

By state, at the default inputs

Estimated cost per month, with this page's default inputs and each state's reference prices (EIA reference 2025–26, data as of 2026-09-26).

US average$26.5018.4¢/kWh
Alabama$22.3215.5¢/kWh
Alaska$36.0025.0¢/kWh
Arizona$21.6015.0¢/kWh
Arkansas$18.7213.0¢/kWh
California$46.0832.0¢/kWh
Colorado$23.0416.0¢/kWh
Connecticut$43.2030.0¢/kWh
Delaware$24.4817.0¢/kWh
District of Columbia$27.3619.0¢/kWh
Florida$21.6015.0¢/kWh
Georgia$20.8814.5¢/kWh
Hawaii$60.4842.0¢/kWh
Idaho$17.2812.0¢/kWh
Illinois$24.4817.0¢/kWh
Indiana$22.3215.5¢/kWh
Iowa$19.4413.5¢/kWh
Kansas$20.8814.5¢/kWh
Kentucky$18.7213.0¢/kWh
Louisiana$18.0012.5¢/kWh
Maine$37.4426.0¢/kWh
Maryland$27.3619.0¢/kWh
Massachusetts$41.7629.0¢/kWh
Michigan$28.0819.5¢/kWh
Minnesota$22.3215.5¢/kWh
Mississippi$19.4413.5¢/kWh
Missouri$18.7213.0¢/kWh
Montana$18.7213.0¢/kWh
Nebraska$17.2812.0¢/kWh
Nevada$21.6015.0¢/kWh
New Hampshire$38.8827.0¢/kWh
New Jersey$31.6822.0¢/kWh
New Mexico$21.6015.0¢/kWh
New York$36.0025.0¢/kWh
North Carolina$20.8814.5¢/kWh
North Dakota$16.5611.5¢/kWh
Ohio$23.7616.5¢/kWh
Oklahoma$18.7213.0¢/kWh
Oregon$20.8814.5¢/kWh
Pennsylvania$26.6418.5¢/kWh
Rhode Island$41.7629.0¢/kWh
South Carolina$21.6015.0¢/kWh
South Dakota$18.7213.0¢/kWh
Tennessee$19.4413.5¢/kWh
Texas$22.3215.5¢/kWh
Utah$17.2812.0¢/kWh
Vermont$31.6822.0¢/kWh
Virginia$22.3215.5¢/kWh
Washington$17.2812.0¢/kWh
West Virginia$22.3215.5¢/kWh
Wisconsin$25.2017.5¢/kWh
Wyoming$18.0012.5¢/kWh

Questions

FAQ

How much does a heated bathroom floor cost per month?

At the US-average rate of 18.4¢/kWh, 40 sq ft at 12 W per sq ft on 8 hours a day with a 0.5 duty cycle uses 58 kWh and costs an estimated $10.60 a month. 100 sq ft on the same schedule costs $26.50.

Electric vs hydronic radiant?

Hydronic floors circulate hot water from a boiler or water heater, so their running cost follows that fuel: gas, propane or a heat pump. This calculator covers electric mats and cables only. To compare fuels per unit of heat, use the Natural Gas vs Electric Heating Cost calculator.

Is radiant floor heating efficient?

It turns all its electricity into heat, like any resistance heater, and a warm floor can feel comfortable at a lower air temperature. Per unit of heat, though, it costs the same as baseboard. Heating 1,500 sq ft for 12 hours a day would cost about $596.16 a month at the US-average rate.

Should I leave it on all day?

Use the thermostat's schedule. Cost scales directly with hours: 16 hours a day costs twice as much as 8.

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