Short answer: Most built-in electric fireplaces draw about 1,500 watts on full heat at 120 volts. At the 2026 U.S. average residential rate of about 18.2 cents per kilowatt-hour (EIA), that is roughly 27 cents an hour. Wired for 240 volts, the same fireplaces draw 2,500 to 3,000 watts and cost roughly 46 to 55 cents an hour on full heat. Running the flame with the heater off costs very little. Below are the real wattages for the fireplaces we carry, the formula, and how to work out your own number from your electric bill.
The formula
Every electric fireplace heater turns electricity into heat the same way, so the math is simple:
Cost per hour = watts ÷ 1,000 × your electricity rate (in dollars per kWh)
Example: a 1,500 W heater at $0.1821 per kWh. 1,500 ÷ 1,000 = 1.5 kWh per hour. 1.5 × $0.1821 = $0.27 per hour.
Two rates are used throughout this article, both from the U.S. Energy Information Administration's October 2026 Short-Term Energy Outlook:
- 18.21¢/kWh: EIA's 2026 average residential price for the United States.
- 29.06¢/kWh: EIA's 2026 average for New England, one of the highest-cost regions.
The 2026 figures combine recorded months with EIA's estimate for the rest of the year. Your own rate may be higher or lower, so swap it in. The section further down shows how to find it.
What our electric fireplaces cost to run, per hour
Wattages come from each manufacturer's manual or published specifications (sources at the end). Costs assume the heater runs continuously at that setting, which is the most it can cost. In practice the thermostat cycles the heater off once the room warms up, so real costs are usually lower.
| Fireplace and setting | Watts | Heat (approx.) | Per hour at 18.2¢ | Per hour at 29.1¢ |
|---|---|---|---|---|
| Napoleon Astound, ECO mode at 120 V (about half power) | about 750 | about 2,560 BTU | about 14¢ | about 22¢ |
| Dimplex Revillusion 36, 120 V | 1,300 | 4,400 BTU | 24¢ | 38¢ |
| SimpliFire Scion or Triton, 120 V | 1,400 | 5,000 BTU | 26¢ | 41¢ |
| Dimplex Ignite XL, Napoleon Astound or SimpliFire Allusion Platinum, 120 V | 1,500 | 5,100 BTU | 27¢ | 44¢ |
| Dimplex Ignite XL, 240 V | 2,500 | 8,530 BTU | 46¢ | 73¢ |
| Dimplex Revillusion 36, 240 V | 2,575 | 8,800 BTU | 47¢ | 75¢ |
| SimpliFire Scion or Triton, 240 V | 2,800 | 10,000 BTU | 51¢ | 81¢ |
| Napoleon Astound, 240 V | 3,000 | 10,000 BTU | 55¢ | 87¢ |
The SimpliFire Allusion Platinum is a 120 V-only fireplace according to SimpliFire's installation manual, so it has no 240 V row. Napoleon describes Astound's ECO mode as running the heater at half power but does not publish an exact wattage for it, so that row is an estimate.
What it costs over a month
Say you run the fireplace four hours every evening for 30 days, 120 hours in total. If the heater ran the whole time on full, the ceiling would be:
| Setting | Energy used | Month at 18.2¢ | Month at 29.1¢ |
|---|---|---|---|
| 1,500 W heater (120 V) | 180 kWh | about $33 | about $52 |
| 2,500 W heater (Ignite XL at 240 V) | 300 kWh | about $55 | about $87 |
| 3,000 W heater (Astound at 240 V) | 360 kWh | about $66 | about $105 |
Treat these as worst cases. If the heater only runs half the time because the thermostat is doing its job, halve them. If you run the flame with the heat off most evenings, the cost drops to almost nothing.
The flame alone costs very little
Modern electric fireplaces make the flame with LEDs, and the heater is controlled separately. On the Dimplex Ignite XL and Revillusion, the Napoleon Astound and the SimpliFire Allusion Platinum, you can run the flame with the heater off.
Manufacturers rarely publish a flame-only wattage for fireplaces that include a heater, so we can't give you a verified figure for each model. The best indication comes from fireplaces that have no heater at all. SimpliFire's Forum outdoor fireplaces are flame-only and are rated at 36 watts. At 18.2¢ per kWh that is under 1 cent an hour, or about 79 cents for the 120-hour month above. A heater-equipped model running its flame alone won't match that exactly, but it shows the scale: the heater is what drives the cost, not the fire.
That matters if you mostly want the look. A fireplace used for ambiance on summer evenings, in a warm bedroom, or under a TV adds very little to the electric bill.
Does 240 volts cost more?
Per hour, yes, because the heater draws more power. Per unit of heat, no. Electric resistance heat delivers about 3,412 BTU for every kilowatt-hour, at any voltage. At 18.2¢ per kWh, every 1,000 BTU costs about 5.3 cents, whether it comes from a 120 V or a 240 V circuit.
So 240 V doesn't make heat more expensive. It lets the fireplace produce more of it when you need it. Run on 240 V with the thermostat set to the same temperature, the heater reaches that temperature sooner and then cycles off.
The real cost of 240 V is upfront: a new circuit from your panel, run by a licensed electrician before the wall is closed. Our electric fireplace electrical requirements guide covers that decision.
A wider fireplace doesn't cost more to run
Within a series, width usually changes the look, not the heater. The Dimplex Ignite XL carries the same electrical rating at 50, 60, 74 and 100 inches. The Napoleon Astound manual gives the same 1,500 W and 3,000 W ratings for the 50, 62, 74 and 96-inch models. Dimplex lists the same heat output for every Revillusion size.
So you can choose the width that suits the wall without worrying about the electric bill. If you want more heat, the lever is voltage, not size.
Is it cheaper than turning up the furnace?
It depends on how your home is heated and what you pay for that fuel, so there isn't one honest answer for everyone. Two things are worth knowing:
- An electric fireplace only saves money if you heat less of the house. Running it in the family room while the main thermostat stays at the same setting adds cost. Lowering the main thermostat a few degrees and warming the room you're in is where the savings come from, if there are any.
- It is supplemental heat. At 5,000 to 10,000 BTU, these fireplaces warm a room. They are not designed to heat a home. If you need a fireplace that does serious heating, compare a gas fireplace, which typically puts out several times more heat. Our gas fireplace sizing guide shows the numbers.
How to find your real electricity rate
The "price per kWh" printed on a bill is often just the supply charge. Delivery charges are added on top and are usually billed per kWh too. To get your all-in rate:
- Take the total amount of a recent winter bill.
- Divide it by the kilowatt-hours used that month.
- Use that number in the formula above.
This slightly overstates the rate because fixed monthly fees are included, which keeps your estimate on the safe side. If you have time-of-use pricing, use the rate for the hours you'll actually run the fireplace, usually the evening.
Checklist: choosing with running cost in mind
- Mostly want the look? Any model works. Running cost with the heater off is negligible, so choose on appearance, depth and fit.
- Want real warmth in one room? Look at a dual-voltage model and plan for 240 V. It costs more per hour on full heat, but no more per unit of heat.
- Want to keep costs predictable? Use the thermostat, ECO or low heat setting where your model has one, and a timer if it has one.
- High electricity rates where you live? Run the numbers at your own rate before deciding between electric and gas.
- Can't add a new circuit? Pick a model that performs well at 120 V. The Allusion Platinum, for example, is designed for 120 V only and can be plugged in or hardwired.
Common questions
How much does an electric fireplace add to a monthly bill?
Running a 1,500 W heater on full for four hours a night costs up to about $33 a month at the 2026 U.S. average rate, and up to about $52 at New England rates. With the thermostat cycling the heater, or with the heat off some nights, it will usually be less.
Is it expensive to leave the flame on?
No. LED flame effects use a small fraction of the power the heater does. A flame-only fireplace like the SimpliFire Forum is rated at 36 watts, under a cent an hour at average U.S. rates.
Do electric fireplaces waste heat up a chimney?
No. There is no chimney or vent. All the electricity the heater uses ends up as heat in the room.
Will a bigger fireplace raise my bill?
Not within the same series. The heater rating is usually the same across widths. Check the manual for the exact model you're considering.
Next step
Browse the electric fireplaces we carry, or go straight to a series: Dimplex Ignite XL, Dimplex Revillusion, Napoleon Astound or SimpliFire. Not sure whether 120 V or 240 V makes sense for your room? Use our free electric fireplace sizing check, or contact us with the model and your wall details, and we'll confirm the electrical requirement against the manufacturer's manual before you order.
Sources
- U.S. Energy Information Administration, Short-Term Energy Outlook, October 2026, Table 7c: U.S. and New England residential electricity prices.
- Dimplex, Ignite XL Installation and User's Guide, document 7215520100R06: electrical rating 1,500 W at 120 V and 2,500 W at 240 V, same rating for all widths.
- Dimplex published specifications, Revillusion 36 built-in firebox: 1,300 W at 120 V and 2,575 W at 240 V.
- Napoleon, Astound Built-in Series Installation and Operation Manual, W415-4170 (NEFB50/62/74/96AB): 1,500 W at 120 V, 3,000 W at 240 V, ECO mode at half heat.
- SimpliFire, Allusion Platinum Owner's and Installation Manual, 2044-980 Rev. L: 120 V, 1,500 W, 12.5 A.
- SimpliFire 2026 Retail Price Book: Scion and Triton 1,400 W at 120 V and 2,800 W at 240 V; Forum 36 W, no heat.
Costs are estimates for planning, calculated from manufacturer ratings and EIA average prices. Your bill depends on your utility's rates, how long the heater runs and your thermostat setting. Electrical work should follow the manufacturer's manual and local code and be done by a licensed electrician.
