The short answer
A 50 sq ft electric heated floor at 12 W per sq ft draws 600 W and costs about 11 cents an hour at the U.S. average electricity rate of 18.16¢ per kWh (August 2026). Heating 4 hours a day, that's $13.08 a month, or $65.38 over a 5-month heating season.
The same floor in every state
50 sq ft at 12 W per sq ft, 4 hours a day, 30 days a month for 5 months, at each state's average residential rate (August 2026).
| Alabama | $11.76 | $58.79 | 16.33¢ |
|---|---|---|---|
| Alaska | $21.18 | $105.88 | 29.41¢ |
| Arizona | $10.84 | $54.18 | 15.05¢ |
| Arkansas | $10.35 | $51.73 | 14.37¢ |
| California | $21.42 | $107.10 | 29.75¢ |
| Colorado | $12.36 | $61.81 | 17.17¢ |
| Connecticut | $17.65 | $88.24 | 24.51¢ |
| Delaware | $13.46 | $67.32 | 18.70¢ |
| District of Columbia | $18.71 | $93.53 | 25.98¢ |
| Florida | $10.79 | $53.96 | 14.99¢ |
| Georgia | $11.45 | $57.24 | 15.90¢ |
| Hawaii | $33.97 | $169.85 | 47.18¢ |
| Idaho | $9.63 | $48.13 | 13.37¢ |
| Illinois | $13.91 | $69.55 | 19.32¢ |
| Indiana | $12.25 | $61.27 | 17.02¢ |
| Iowa | $12.28 | $61.42 | 17.06¢ |
| Kansas | $11.14 | $55.69 | 15.47¢ |
| Kentucky | $9.94 | $49.68 | 13.80¢ |
| Louisiana | $9.27 | $46.33 | 12.87¢ |
| Maine | $23.12 | $115.60 | 32.11¢ |
| Maryland | $15.41 | $77.04 | 21.40¢ |
| Massachusetts | $21.95 | $109.73 | 30.48¢ |
| Michigan | $16.55 | $82.76 | 22.99¢ |
| Minnesota | $12.38 | $61.92 | 17.20¢ |
| Mississippi | $10.39 | $51.95 | 14.43¢ |
| Missouri | $11.53 | $57.67 | 16.02¢ |
| Montana | $11.21 | $56.05 | 15.57¢ |
| Nebraska | $9.75 | $48.74 | 13.54¢ |
| Nevada | $9.16 | $45.79 | 12.72¢ |
| New Hampshire | $19.90 | $99.50 | 27.64¢ |
| New Jersey | $17.72 | $88.60 | 24.61¢ |
| New Mexico | $11.89 | $59.44 | 16.51¢ |
| New York | $20.63 | $103.14 | 28.65¢ |
| North Carolina | $10.76 | $53.82 | 14.95¢ |
| North Dakota | $9.58 | $47.92 | 13.31¢ |
| Ohio | $13.95 | $69.77 | 19.38¢ |
| Oklahoma | $10.67 | $53.35 | 14.82¢ |
| Oregon | $11.46 | $57.31 | 15.92¢ |
| Pennsylvania | $15.67 | $78.37 | 21.77¢ |
| Rhode Island | $20.29 | $101.45 | 28.18¢ |
| South Carolina | $11.35 | $56.74 | 15.76¢ |
| South Dakota | $10.91 | $54.54 | 15.15¢ |
| Tennessee | $9.66 | $48.31 | 13.42¢ |
| Texas | $11.46 | $57.28 | 15.91¢ |
| Utah | $9.58 | $47.92 | 13.31¢ |
| Vermont | $17.16 | $85.82 | 23.84¢ |
| Virginia | $12.70 | $63.50 | 17.64¢ |
| Washington | $10.53 | $52.67 | 14.63¢ |
| West Virginia | $11.74 | $58.72 | 16.31¢ |
| Wisconsin | $13.98 | $69.88 | 19.41¢ |
| Wyoming | $10.39 | $51.95 | 14.43¢ |
How it works
The formula
kWh = watts × hours × days ÷ 1,000
cost = kWh × rate
Assumptions
- Watts per sq ft: 12 for WarmlyYours' 120 V Environ mats and 15 for its TempZone mats, from the maker's product pages. Your mat's label has its own figure.
- "Hours" is time the mat is heating. Its thermostat switches it off once the floor is warm, so it's usually less than the time it's on.
- At 120 V, amps = watts ÷ 120. A 15 A circuit should carry at most 12 A (80%); above that the mat needs a 20 A circuit, a 240 V mat or more than one circuit.
Worked example: a bathroom floor
- 50 sq ft × 12 W = 600 W
- 600 W × 4 h × 30 days ÷ 1,000 = 72 kWh
- × 18.16¢ = $13.08 a month
Ways to cut the cost
- Use a programmable thermostat so the floor is warm when you get up and off while you're out.
- Put insulation under the mat on a concrete slab; less heat goes into the ground.
- Turn the floor setting down: a few degrees warmer than the room feels warm underfoot.
Questions people ask
How much does it cost to run a heated floor?
A 50 sq ft bathroom floor at 12 W per sq ft draws 600 W, about 11 cents an hour at the U.S. average of 18.16¢ per kWh (EIA, August 2026). Four hours a day comes to $13.08 a month: $9.16 in Nevada and $33.97 in Hawaii.
Is it expensive to leave floor heating on all the time?
Running flat out 24 hours, the same floor would cost about $78.45 a month. In practice its thermostat cycles it, and a programmable one that warms the floor only for mornings and evenings costs far less.
How many watts per square foot is floor heating?
WarmlyYours rates its 120 V Environ mats at 12 W per sq ft and its TempZone mats at 15 W per sq ft. Check the mat's label; slab-heating products can be 20 W or more.
Can floor heating heat a whole room?
In a well-insulated bathroom or kitchen, often; in most rooms it's for comfort, with the house heat doing the rest. Size the mat to the floor you walk on, not under cabinets or the tub.