How Much Does It Cost to Run a Light: Daily, Monthly, and Yearly Expenses
ZacharyWilliamIf you have ever wondered whether leaving a light on is “wasting money,” you are not alone. The good news: with modern LED bulbs, the actual cost to run most household lights is a lot lower than most people think. In this guide, we will walk through real numbers so you can see the daily, monthly, and yearly cost of running a light in your home.
- A typical 9W LED (60W equivalent) costs roughly $0.01 per day if used 4 hours a day.
- The same brightness from a 60W incandescent bulb costs about $0.04–$0.05 per day at 4 hours a day.
- Over a full year, switching one bulb from 60W incandescent to 9W LED can save around $10–$15 per bulb, depending on your local rates and usage.
- Typical Cost to Run Common Lights
- How Electricity Billing Works (kWh & Formula)
- Cost Examples: LED vs. Incandescent Bulbs
- Always-On Lights: Porch, Hallway, and Night Lights
- Why Your State’s Electricity Rate Changes the Math
- How to Reduce Lighting Costs Without Living in the Dark
- Running Lights Off-Grid with a Portable Power Station (UDPOWER)
- FAQs About the Cost of Running a Light
1. Typical Cost to Run Common Lights
To keep things simple, the numbers below assume:
- Electricity price: $0.18 per kWh (close to the current U.S. residential average).
- Usage: 4 hours per day, which is typical for living-room or bedroom lights.
- Bulb types: modern LEDs, halogen bulbs, and older incandescent bulbs.
| Bulb type | Power (W) | Daily cost (4 hours, cents) |
Monthly cost (30 days, $) |
Yearly cost (365 days, $) |
|---|---|---|---|---|
| LED night light | 5W | 0.36¢ | $0.11 | $1.31 |
| LED bulb (60W equivalent) | 9W | 0.65¢ | $0.19 | $2.37 |
| LED bulb (100W equivalent) | 15W | 1.08¢ | $0.32 | $3.94 |
| Halogen bulb (60W type) | 43W | 3.10¢ | $0.93 | $11.30 |
| Incandescent bulb (60W) | 60W | 4.32¢ | $1.30 | $15.77 |
| Incandescent bulb (100W) | 100W | 7.20¢ | $2.16 | $26.28 |
All numbers are approximate and based on an electricity rate of $0.18/kWh. Actual costs vary by utility and state.
The key takeaway: LEDs are so efficient that their cost is usually measured in fractions of a cent per day, while older incandescent bulbs can be 5–7 times more expensive to operate for the same brightness.
2. How Electricity Billing Works (kWh & Formula)
On your electric bill, you are charged by the kilowatt-hour (kWh). One kWh is the energy used by a 1,000-watt appliance running for 1 hour.
Basic formula to estimate light cost:
Cost = (Watts ÷ 1000) × Hours Used × Rate per kWh
- Watts: bulb power rating (for example, 9W, 60W).
- Hours Used: how long the light is on per day or per month.
- Rate per kWh: your electricity price (for example, $0.18/kWh).
To get monthly or yearly costs, you simply multiply the daily cost:
- Monthly cost ≈ daily cost × 30
- Yearly cost ≈ daily cost × 365
3. Cost Examples: LED vs. Incandescent Bulbs
Example 1: 9W LED bulb (60W equivalent)
Let us say you have a 9W LED bulb in your living room and you use it 8 hours per day.
- Power: 9W = 0.009 kW
- Daily energy use: 0.009 kW × 8 h = 0.072 kWh
- Daily cost at $0.18/kWh: 0.072 × 0.18 ≈ $0.013/day (about 1.3¢)
- Monthly cost (30 days): ≈ $0.39/month
- Yearly cost: ≈ $4.73/year
Example 2: 60W incandescent bulb
Now compare that to an older 60W incandescent bulb used the same 8 hours per day.
- Power: 60W = 0.06 kW
- Daily energy use: 0.06 kW × 8 h = 0.48 kWh
- Daily cost at $0.18/kWh: 0.48 × 0.18 ≈ $0.086/day (about 8.6¢)
- Monthly cost (30 days): ≈ $2.59/month
- Yearly cost: ≈ $31.39/year
Swapping just one incandescent for an LED can easily save around $25–$30 over a few years, and households usually have dozens of bulbs.
4. Always-On Lights: Porch, Hallway, and Night Lights
Some lights stay on for long stretches: porch lights, hallway night lights, or lights used for security. Here is what it costs to run common bulbs 24 hours a day at $0.18/kWh.
| Bulb type | Power (W) | Daily cost (24 hours, $) |
Monthly cost (30 days, $) |
Yearly cost (365 days, $) |
|---|---|---|---|---|
| LED night light | 5W | $0.02 | $0.65 | $7.88 |
| LED bulb (60W equivalent) | 9W | $0.04 | $1.17 | $14.19 |
| LED bulb (100W equivalent) | 15W | $0.06 | $1.94 | $23.65 |
| Halogen bulb (60W type) | 43W | $0.19 | $5.57 | $67.80 |
| Incandescent bulb (60W) | 60W | $0.26 | $7.78 | $94.61 |
| Incandescent bulb (100W) | 100W | $0.43 | $12.96 | $157.68 |
For always-on lights, using LED bulbs keeps costs modest. Using older 60W–100W bulbs 24/7 can quietly add close to $100–$150 per bulb per year to your bill.
5. Why Your State’s Electricity Rate Changes the Math
Not everyone pays the same for electricity. In December 2025, average residential rates in the U.S. ranged from roughly about 11–12¢ per kWh in the lowest-cost states to over 40¢ per kWh in the highest-cost states, with a national residential average around 18¢ per kWh.
The formula is the same — only the rate per kWh changes. For example, let us look at a 60W bulb used 4 hours per day:
- At 12¢/kWh: yearly cost ≈ $10
- At 18¢/kWh: yearly cost ≈ $16
- At 42¢/kWh: yearly cost ≈ $37
To get accurate numbers for your home, grab your utility bill, find the “price per kWh” line, and plug it into the formula in the previous section.
State-by-state cost to run a 60W bulb for 4 hours per day
Using the same 60W example and 4 hours of daily use, the table below shows how much it costs to run that one bulb in each U.S. state, based on the latest average residential electricity prices from the U.S. Energy Information Administration (September 2025).
| Wattage (W) | Usage (Hrs/Day) | State | Rate (¢/kWh) | Daily Cost | Monthly Cost | Yearly Cost |
|---|---|---|---|---|---|---|
| 60 | 4 | Alabama | 16.43 | $0.04 | $1.18 | $14.39 |
| 60 | 4 | Alaska | 27.16 | $0.07 | $1.96 | $23.79 |
| 60 | 4 | Arizona | 15.27 | $0.04 | $1.10 | $13.38 |
| 60 | 4 | Arkansas | 13.79 | $0.03 | $0.99 | $12.08 |
| 60 | 4 | California | 32.04 | $0.08 | $2.31 | $28.07 |
| 60 | 4 | Colorado | 16.70 | $0.04 | $1.20 | $14.63 |
| 60 | 4 | Connecticut | 30.48 | $0.07 | $2.19 | $26.70 |
| 60 | 4 | Delaware | 18.12 | $0.04 | $1.30 | $15.87 |
| 60 | 4 | Florida | 15.76 | $0.04 | $1.13 | $13.81 |
| 60 | 4 | Georgia | 15.30 | $0.04 | $1.10 | $13.40 |
| 60 | 4 | Hawaii | 39.54 | $0.09 | $2.85 | $34.64 |
| 60 | 4 | Idaho | 12.50 | $0.03 | $0.90 | $10.95 |
| 60 | 4 | Illinois | 19.05 | $0.05 | $1.37 | $16.69 |
| 60 | 4 | Indiana | 17.33 | $0.04 | $1.25 | $15.18 |
| 60 | 4 | Iowa | 14.79 | $0.04 | $1.06 | $12.96 |
| 60 | 4 | Kansas | 15.20 | $0.04 | $1.09 | $13.32 |
| 60 | 4 | Kentucky | 13.56 | $0.03 | $0.98 | $11.88 |
| 60 | 4 | Louisiana | 12.36 | $0.03 | $0.89 | $10.83 |
| 60 | 4 | Maine | 27.98 | $0.07 | $2.01 | $24.51 |
| 60 | 4 | Maryland | 21.05 | $0.05 | $1.52 | $18.44 |
| 60 | 4 | Massachusetts | 30.41 | $0.07 | $2.19 | $26.64 |
| 60 | 4 | Michigan | 21.20 | $0.05 | $1.53 | $18.57 |
| 60 | 4 | Minnesota | 17.10 | $0.04 | $1.23 | $14.98 |
| 60 | 4 | Mississippi | 13.97 | $0.03 | $1.01 | $12.24 |
| 60 | 4 | Missouri | 15.84 | $0.04 | $1.14 | $13.88 |
| 60 | 4 | Montana | 14.64 | $0.04 | $1.05 | $12.82 |
| 60 | 4 | Nebraska | 13.85 | $0.03 | $1.00 | $12.13 |
| 60 | 4 | Nevada | 11.95 | $0.03 | $0.86 | $10.47 |
| 60 | 4 | New Hampshire | 27.82 | $0.07 | $2.00 | $24.37 |
| 60 | 4 | New Jersey | 23.39 | $0.06 | $1.68 | $20.49 |
| 60 | 4 | New Mexico | 16.52 | $0.04 | $1.19 | $14.47 |
| 60 | 4 | New York | 27.23 | $0.07 | $1.96 | $23.85 |
| 60 | 4 | North Carolina | 15.12 | $0.04 | $1.09 | $13.25 |
| 60 | 4 | North Dakota | 13.66 | $0.03 | $0.98 | $11.97 |
| 60 | 4 | Ohio | 17.61 | $0.04 | $1.27 | $15.43 |
| 60 | 4 | Oklahoma | 14.79 | $0.04 | $1.06 | $12.96 |
| 60 | 4 | Oregon | 15.96 | $0.04 | $1.15 | $13.98 |
| 60 | 4 | Pennsylvania | 20.46 | $0.05 | $1.47 | $17.92 |
| 60 | 4 | Rhode Island | 28.30 | $0.07 | $2.04 | $24.79 |
| 60 | 4 | South Carolina | 15.34 | $0.04 | $1.10 | $13.44 |
| 60 | 4 | South Dakota | 14.76 | $0.04 | $1.06 | $12.93 |
| 60 | 4 | Tennessee | 13.29 | $0.03 | $0.96 | $11.64 |
| 60 | 4 | Texas | 15.84 | $0.04 | $1.14 | $13.88 |
| 60 | 4 | Utah | 14.12 | $0.03 | $1.02 | $12.37 |
| 60 | 4 | Vermont | 23.92 | $0.06 | $1.72 | $20.95 |
| 60 | 4 | Virginia | 16.62 | $0.04 | $1.20 | $14.56 |
| 60 | 4 | Washington | 13.79 | $0.03 | $0.99 | $12.08 |
| 60 | 4 | West Virginia | 16.14 | $0.04 | $1.16 | $14.14 |
| 60 | 4 | Wisconsin | 18.73 | $0.04 | $1.35 | $16.41 |
| 60 | 4 | Wyoming | 15.00 | $0.04 | $1.08 | $13.14 |
Data source: U.S. Energy Information Administration, Electric Power Monthly, Table 5.6.A (Average Price of Electricity to Ultimate Customers by End-Use Sector, by State, September 2025) . Costs assume a single 60W bulb used 4 hours per day (0.24 kWh/day) at each state's average residential rate.
6. How to Reduce Lighting Costs Without Living in the Dark
You do not need to sit in the dark to keep your electric bill under control. These practical steps focus on high-impact changes:
1) Switch to LED bulbs everywhere
- Replace 60W and 100W incandescent bulbs with 7–15W LEDs.
- Look for the lumen rating (brightness) rather than just wattage.
- Choose warm white (2700–3000K) for cozy spaces and neutral/cool white for task areas.
2) Target the biggest “on-time” bulbs first
- Hallways, kitchens, porch lights, and living rooms often run the longest.
- Upgrading these bulbs first gives you the fastest payback on your LED investment.
3) Use smart controls where it makes sense
- Motion sensors in closets, garages, and outdoor areas so lights turn off automatically.
- Smart switches or plugs for schedules (for example, porch lights from sunset to midnight).
4) Make use of natural light
- Open blinds and curtains during the day to reduce the need for artificial lighting.
- Use lighter wall colors in rooms that feel dark; they reflect more light.
5) Consider light placement instead of more watts
- A well-placed desk lamp uses far less energy than flooding a whole room with overhead light.
- Use task lighting in kitchens and workspaces so you can keep ambient lighting lower.
7. Running Lights Off-Grid with a Portable Power Station (UDPOWER)
For everyday use, your lights run from the grid. But during power outages, camping trips, or vanlife, a portable power station can keep your LED lights on without a gas generator. This is where LiFePO₄-based stations like UDPOWER can be useful.
At a high level, runtime from a battery is: Runtime (hours) ≈ Battery capacity (Wh) ÷ Load (W). Real-world runtimes will be slightly lower due to inverter and conversion losses, but it is a reliable starting point.
192Wh capacity, 200W pure sine wave, about 5.4 lbs.
Example runtime: a single 9W LED bulb could run for roughly 21 hours (192Wh ÷ 9W), enough for several evenings of lighting on one charge.
Learn more about UDPOWER C200
256Wh capacity, 400W output (800W surge), compact and light enough for camping.
Example runtime: a 9W LED could run for about 28 hours (256Wh ÷ 9W), or you could power a small string of LED lights for an evening plus phone charging and other essentials.
Learn more about UDPOWER C400
596Wh LiFePO₄, 600W rated (1,200W peak), designed for weekend trips and small home backup needs.
Example runtime: a 9W LED could run for around 66 hours (596Wh ÷ 9W), which is plenty to keep several rooms lit during a multi-day outage.
Learn more about UDPOWER C600
1,190Wh capacity, 1,200W rated output (up to 1,800W surge), LiFePO₄ battery with 4,000+ cycles and UPS mode for sub-10ms switchover.
Example runtime: a 9W LED could run for roughly 132 hours (1,190Wh ÷ 9W) — more than 5 days of continuous light — while still leaving plenty of capacity for routers, laptops, and small appliances.
Learn more about UDPOWER S1200
If you are mainly focused on keeping LED lights and a few electronics on during power outages, smaller units like the C200 or C400 are often enough. If you also want to run routers, laptops, fans, or a small fridge, the C600 or S1200 offer more comfortable runtime and higher output capacity.
8. FAQs About the Cost of Running a Light
Is it expensive to leave a light on all night?
With a modern LED bulb, leaving a single light on all night is usually very inexpensive. For example, a 9W LED running 8 hours costs around 1–2 cents at typical U.S. rates. However, leaving many lights on in multiple rooms can add up, so it is still worth turning off lights you are not using.
What uses more electricity: lights or big appliances?
In most homes, large appliances (HVAC systems, electric heaters, ovens, dryers, and refrigerators) dominate energy use. Lighting used to be a major chunk of the bill in the incandescent era, but with LED bulbs it usually becomes a relatively small share of total consumption.
Are LED bulbs always cheaper to run than CFL or halogen bulbs?
Yes, in most cases. LEDs typically use less power for the same brightness compared to compact fluorescent (CFL) or halogen bulbs, and they last longer. That means lower electricity costs and fewer bulb replacements over time.
How can I calculate the cost for my specific bulb?
Look at the wattage printed on the bulb or packaging, estimate how many hours per day it is on, and check your electric bill for the exact price per kWh. Then plug those numbers into the formula: Cost = (Watts ÷ 1000) × Hours × Rate per kWh.
Is it worth replacing a working incandescent bulb with an LED?
If the bulb sees a lot of use (for example, living rooms, kitchens, porch lights), the savings from switching to LED can quickly outweigh the cost of the new bulb. For rarely used fixtures, you can wait until the old bulb burns out before replacing it.
The bottom line: once you understand the numbers, you will see that efficient LED lighting is one of the easiest, lowest-effort ways to save on your electric bill — and it makes backup planning with a portable power station much more practical.
