For a typical LED bulb used three hours daily, electricity costs about $1-$3 per year; an incandescent bulb with similar brightness can cost $7-$20. The light bulb cost to run depends mainly on wattage, daily use, and the local electricity rate.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| 9W LED, annual use | $1.00 | $1.60 | $3.00 | 3 hours daily; electricity at $0.10-$0.30 per kWh |
| 60W incandescent, annual use | $6.60 | $10.50 | $19.70 | Similar brightness to a 9W LED |
| 10 LED bulbs, annual use | $10 | $16 | $30 | Each used 3 hours daily |
Assumptions: 365 days of use, 3 hours daily, and electricity rates of $0.10, $0.16, or $0.30 per kWh.
Annual electricity cost for one LED bulb
A standard 9W LED running three hours per day uses about 9.9 kilowatt-hours (kWh) in a year. At the approximate U.S. residential rate of $0.16 per kWh, that works out to roughly $1.60 annually, or about 13 cents per month. A bulb used eight hours each day costs about $4.20 per year at the same rate.
For most households, hours of use and the power company’s rate matter more than small differences between LED models. The estimate covers electricity only, not the purchase or replacement price of the bulb.
What electricity and bulb use add to the bill
The running charge is based on energy consumed, not the bulb’s brightness alone. A bulb labeled 60W uses 60 watts while operating; LED packaging often lists both its actual wattage and its incandescent-equivalent brightness. For a cost estimate, use actual watts.
| Bulb and use | Energy per year | At $0.10/kWh | At $0.16/kWh | At $0.30/kWh |
|---|---|---|---|---|
| 9W LED, 3 hours/day | 9.9 kWh | $0.99 | $1.58 | $2.96 |
| 12W LED, 5 hours/day | 21.9 kWh | $2.19 | $3.50 | $6.57 |
| 60W incandescent, 3 hours/day | 65.7 kWh | $6.57 | $10.51 | $19.71 |
| 10W CFL, 3 hours/day | 11.0 kWh | $1.10 | $1.75 | $3.29 |
At $0.16 per kWh, each 1,000 watts used for one hour costs about 16 cents. A simple calculation for annual expense is .
Wattage and daily hours change the total
Doubling a bulb’s wattage or its daily operating time approximately doubles its energy charge. A 9W LED used for one hour each day costs about 53 cents a year at $0.16 per kWh; the same bulb left on for eight hours daily costs about $4.20. Motion sensors, dimmers, and timers can reduce use when they actually shorten operating hours.
Brightness can also affect the comparison. A 60W-equivalent LED commonly uses about 8-10W, while a brighter 100W-equivalent model may draw around 14-17W. Compare actual wattage at the needed brightness, rather than comparing bulb labels by equivalent watts.
LED, CFL, and incandescent running prices
LEDs generally use less electricity for comparable light output. At three hours daily and $0.16 per kWh, a 9W LED costs about $1.60 per year, a 10W compact fluorescent lamp (CFL) about $1.75, and a 60W incandescent about $10.50. A halogen bulb drawing 43W for similar brightness would cost about $7.50 annually under the same assumptions.
Purchase price and service life can change the longer-term comparison: LEDs often cost more upfront than basic incandescent bulbs but usually last much longer. CFLs contain mercury and need appropriate disposal; incandescent bulbs are being phased out of many common U.S. retail categories under federal efficiency rules. For ongoing electricity expense, an LED is usually the least costly of these common options.
Electricity rates vary across U.S. locations
A bulb’s energy use does not change with location, but the price per kWh does. At three hours daily, the 9W LED costs about $0.99 a year at $0.10 per kWh and $2.96 at $0.30. Higher-rate markets, including parts of the Northeast and California, can make the same bulb cost several times more to operate than in lower-rate areas.
Use the total residential rate from a recent electric bill, including delivery charges where they are billed per kWh. Fixed monthly fees do not usually change when a single bulb is switched off, so they should not be assigned to that bulb’s operating cost.
Three household examples show yearly bulb expense
| Example | Calculation | Estimated yearly cost |
|---|---|---|
| Bedroom LED | 9W, 3 hours daily, $0.16/kWh | $1.58 |
| Kitchen LED | 12W, 5 hours daily, $0.20/kWh | $4.38 |
| Garage incandescent | 60W, 2 hours daily, $0.18/kWh | $7.88 |
These examples exclude standby power from smart bulbs, which varies by model and is usually small. A bulb used continuously, such as a porch light left on all night, can have a substantially higher annual charge than one used briefly.
Smart switches and fixtures add separate expenses
Replacing a bulb is usually a simple self-installation, but a new fixture, dimmer, or smart switch adds purchase and possibly labor costs that are separate from the bulb’s electricity use. An electrician may charge roughly $75-$150 per hour, often with a minimum service fee; straightforward switch or fixture work can take about one to two hours, while wiring changes may take longer.
Check that a bulb is compatible with an existing dimmer before installing it. A flickering or buzzing LED may need a compatible dimmer or replacement, adding upfront expense without necessarily increasing the bulb’s rated wattage.
Lower the bill by managing wattage and run time
Replacing frequently used incandescent bulbs with appropriately sized LEDs generally produces the clearest savings. Reducing a 60W bulb to a 9W LED saves about 51 watts while on; used three hours daily at $0.16 per kWh, that is roughly $8.90 in annual electricity savings per bulb.
Turn off lights in empty rooms, use task lighting rather than lighting an entire room, and avoid buying brighter bulbs than the fixture or space requires. Prioritize bulbs with long daily run times when estimating which replacements will save the most.