When thinking about the cost of lighting, it’s important to look beyond just the price of the bulb. The total cost includes both the upfront purchase price and the ongoing cost to power the bulb over time.

In 2020, lighting accounted for about 5% of total energy costs in the average U.S. home, clocking in at about $92 per year just on energy for lighting. For 2025 electricity rates, this average cost is closer to $120 per year (and can reach higher than $270 in areas with expensive electricity rates). The exact amount each household spends varies depending on electricity rates, the number of bulbs in use, their wattage, and how long they are turned on each day.

Daily usage patterns play a significant role in these costs. On average, US households report keeping about 6 light bulbs on for 1 to 4 hours per day, 4 bulbs on for 4 to 8 hours per day, and 2 bulbs on for more than 8 hours per day. In addition, about 40% of homes report leaving at least 1 outdoor light on throughout the night, every night.

To calculate the cost of electricity to operate each light bulb, you multiply the light bulb’s wattage by the number of hours it’s turned on. For example, if a 60-W incandescent light bulb is on for 5 hours per day, it uses 300 Watt-hours of energy per day, which is equal to 0.3 kiloWatt-hours (kWh) per day. At an electricity rate of $0.20 per kWh, that costs about $0.06 per day, or about $22 per year for just one bulb.

Switching to a more efficient bulb can significantly reduce these costs. Replacing that same 60-watt incandescent with a 9-watt LED performing a similar function would reduce annual operating costs to just over $3 per year. That’s an 85% decrease in operating costs. Over time, these savings compound, especially in homes with many frequently used bulbs.

Long-term costs also vary based on how often bulbs need to be replaced. Over a 20,000-hour period, you would typically need one LED, three CFLs, or about twenty incandescent bulbs, based on their average lifespans. This means that even if some bulbs have a lower upfront cost, they can become more expensive over time due to higher energy use and more frequent replacement.