This is the most-asked question I get every fall. A homeowner picks up the phone, hears the price for a professional Christmas light install, and instead of pushing back on the install cost, they push back on what happens next: “What is this going to do to my electric bill?” Below is the real answer, with real numbers from an actual Kill A Watt reading I took on a fully-lit residential install — not a manufacturer marketing claim, not a calculator with optimistic assumptions, an actual amp test.
I am Jason Geiman. I scaled a Christmas light installation business from \,000 to \M+ with four crews, sold it in 2018, and now run Christmas Lights HQ (wholesale gear) and Christmas Lights University (43,000+ contractor community). The amp test in the video below is something I have run on hundreds of houses. The math is below it. Send this article to your customers when they ask — or read it before your next phone qualifier so you have the right answer ready.
The amp test that ends the argument (60 seconds of video)
This is a fully-loaded residential install — 235 feet of C9 LEDs across the roofline and peaks, six strands of mini lights, and a lit wreath. I plugged the whole run into a Kill A Watt meter and measured the actual draw. Here is what happened:
The reading on the meter: 1.34 amps. Whole house. 235 feet of C9, six strands of minis, and a wreath — 1.34 amps. In the incandescent days that exact same install would have been pulling 7 to 10 amps on every house, which is why pro installers had to split residential jobs across two or three different circuits and homeowners genuinely dreaded their December electric bill. With LED, it is one outlet, one circuit, and a number on the bill so small most homeowners cannot find it.
The math: how to calculate your own cost in 60 seconds
Three numbers and you have your answer:
- Watts: what the lights are drawing. Either measure with a Kill A Watt meter (cheapest option, plugs in line with the lights), use volts × amps from a clamp multimeter, or estimate from bulb count and the wattage table below.
- Hours: total run time. Most homeowners run lights about 6 hours per night (5pm to 11pm) for 30–45 nights.
- Rate: what your power company charges per kilowatt-hour. Find it on your bill (look for “cost per kWh” or “rate”). The 2026 U.S. residential average is roughly 17.65 cents per kWh.
The formula: Watts ÷ 1,000 × Hours × Rate = Cost.
Worked example using Jason's amp test: 1.34 amps × 120 volts = 161 watts. 161 ÷ 1,000 = 0.161 kW. 0.161 × 180 hours (6 hrs × 30 nights) = 28.98 kWh. 28.98 × \bash.1765 = \.11 for the entire month.
That is what a fully-lit professional install actually costs the homeowner. Roughly the price of a single grocery-store coffee for the entire season.
LED vs incandescent: the comparison that closes deals
If you are still installing incandescent on residential, you are losing the “but my electric bill” conversation before it starts. Here are the wattages side-by-side — LED on the left, incandescent equivalent on the right.
| Bulb type | LED watts per bulb | Incandescent watts per bulb | LED savings |
|---|---|---|---|
| C9 (pro standard) | ~0.9 W | ~7 W | ~87% less power |
| C7 | ~0.5 W | ~5 W | ~90% less power |
| 5mm mini light | ~0.05 W | ~0.40 W | ~88% less power |
| 100-bulb mini strand | ~5 W | ~40 W | ~87% less power |
Run those wattages through a typical residential install and the difference is dramatic. Here is what an average 2,500 square foot suburban home looks like in both worlds:
| Install size | LED total wattage | Incandescent total wattage | LED monthly cost* | Incandescent monthly cost* |
|---|---|---|---|---|
| Small (roofline only, ~100 ft) | 90 W | 700 W | \.86 | \2.24 |
| Medium (typical 2,500 sq ft: roofline + 2 trees + bushes + wreath) | 230 W | 1,705 W | \.31 | \4.17 |
| Large (4,000 sq ft: full roofline + 4 trees + bushes + wreaths + ridge caps) | 450 W | 3,400 W | \4.30 | \08.05 |
| Commercial / HOA entry | 800 W | 6,500 W | \5.42 | \06.55 |
*Monthly cost = 6 hours/night × 30 nights at the 2026 U.S. average residential rate of 17.65 cents per kWh. Source: U.S. Energy Information Administration.
The medium-home number is the one to memorize: about \ per month on LED versus \4 on incandescent. The LED upgrade pays for itself in electricity savings inside a single season.
Cost by state: where you live changes the answer
The U.S. average is 17.65 cents per kWh, but the spread is huge. Hawaii pays more than three times what North Dakota pays. Here is what the medium 230-watt residential install costs each month in different markets:
| Market | Approx. rate (¢/kWh) | LED medium install: monthly cost | Incandescent equivalent: monthly cost |
|---|---|---|---|
| North Dakota | 11.6¢ | \.82 | \5.72 |
| Idaho | 12.5¢ | \.18 | \8.39 |
| U.S. national average | 17.7¢ | \.31 | \4.17 |
| Connecticut / Massachusetts | ~30¢ | \2.42 | \2.07 |
| California | ~33.8¢ | \4.00 | \03.74 |
| Hawaii | ~42¢ | \7.39 | \28.83 |
The big takeaway: even in the most expensive markets in the country, a magical, full residential LED Christmas light install is under \8 per month. In Hawaii. Where everything costs more than every other state combined.
2026 context: electricity rates are climbing, the LED case gets stronger every year
Residential electricity prices rose roughly 9% year-over-year in early 2026, according to U.S. Energy Information Administration data, and they are projected to keep climbing through the end of the decade. The reason is not Christmas lights. It is AI data centers — one industry analysis projects U.S. data center demand nearly doubling from 80 GW to 150 GW between 2025 and 2028, pulling residential rates up with it. Some grid-adjacent markets have already seen residential bills climb up to 267% over the past five years.
Translation: the dollar gap between LED and incandescent is widening every season. A homeowner who paid \0/month on incandescent last December is going to pay closer to \5 this December, and \0 the December after that. The LED upgrade looks better and better as the years go on.
How to make it even cheaper
If a homeowner still wants to push the cost down, here are the levers that actually move the needle — in order of impact:
- Run the lights fewer hours per night. Cutting from 6 hours/night to 4 hours/night drops the bill by a third — without anyone noticing because most of the “magic hours” are 5pm to 9pm anyway.
- Use a timer. A \5 outdoor timer turns on at dusk and off at 11pm so the lights are not running until sunrise after the homeowner falls asleep. Most pro installers include a timer in every package.
- Run all-LED. If there is even one strand of incandescent left in the install, it is drawing 7–10x the wattage of the rest. Replace it.
- Pre-bulb and pre-clip at the shop, not on the roof. Has nothing to do with operating cost — everything to do with install efficiency. See our pre-bulb and pre-clip workflow guide.
- Skip net lights and big-box minis. They draw more per visible bulb and they fail sooner. Pro 5mm LED mini strands are the gold standard.
How pros use this in the sales conversation
When the homeowner brings up electricity cost on the phone — and they will, on roughly half of qualifier calls — here is the line that works:
“Great question. We use all LED, all C9 pro grade, so the whole install for a house your size runs about \ to \0 a month at our local rate. Less than a Starbucks. It is honestly one of the cheapest things on your electric bill in December.”
Then drop the Kill A Watt anchor: “I actually ran an amp test on a full install last year — 235 feet of C9, six tree strands, a wreath — only 1.3 amps. The whole house.”
That answer ends the objection. The homeowner moves on. Now you are talking about the install date and the deposit, which is where you wanted to be. For the rest of the sales sequence see our kitchen table close guide and our full sales process walkthrough.
The tool that proves the number on the spot
The Kill A Watt meter shown in the video is the single best electrical diagnostic tool for a Christmas light truck. Under \$40, plugs in line with the lights, reads watts and amps directly on the display. I use it for two things: ending the “how much will this cost me” objection on residential sales calls, and diagnosing GFCI tripping on service calls.
This is one of the tools I keep on my full Christmas light installer tools list at ChristmasLights.io/tools — along with the rest of the kit I use in the field (cougar paws, ridge pro, harness, pitch hopper, micro cutters, headlamps, ladders, the works). Buy it once. Keep it in the truck. It pays for itself the first time a homeowner asks about the electric bill.
The gear that delivers the magic at \ per month
The reason a fully-lit, magical, best-house-on-the-block install only costs \ a month is the gear. Pro C9 LED bulbs, 5mm mini light strands, SPT-1 socket wire, Tuff Bulb clips. Big-box gear pulls more power, fails faster, and costs more to run because half the strands die by mid-December and the homeowner replaces them with whatever Home Depot has in stock that week.
Christmas Lights HQ stocks pro C9 LED bulbs with a 5-year warranty, Tuff Bulb clips and shingle tab clips, SPT-1 socket wire for custom cords, Gilbert plugs, and pre-assembled Pro Light Kits ready to ship same-day before 2 PM ET. Free shipping on orders over \49. Use our Christmas light calculator for footage and our bush lighting calculator for residential bushes. Shop the full catalog.
Related Guides
- Why Your Christmas Light GFCI Keeps Tripping (and the Pro Fix)
- C9 LED Christmas Lights: The Complete Contractor's Guide
- Voltage Drop in Christmas Lights: What Every Installer Must Know
- SPT-1 vs SPT-2 Wire: Which Should Contractors Use?
- The Kitchen Table Close: How Pro Christmas Light Contractors Convert Walkthroughs Into Booked Jobs
- How to Sell Christmas Light Installations: A Pro Contractor's Sales Process
- How to Run Power for Christmas Light Installations
FAQ
How much does it actually cost to run Christmas lights for a month?
For a typical medium-sized residential install using all LED bulbs (roofline + 2 trees + bushes + wreath), expect about \ to \0 per month at the 2026 U.S. average rate of 17.65 cents per kWh, run 6 hours per night for 30 nights. A real-world amp test on a fully-lit install showed 1.34 amps, or about 161 watts — \.11 per month.
How much do LED Christmas lights save versus incandescent?
Pro-grade LED Christmas lights draw about 85–90% less power than incandescent equivalents. C9 LED bulbs are roughly 0.9 watts each vs about 7 watts for C9 incandescent. A medium install that costs \/month on LED would cost roughly \4/month on incandescent. The LED upgrade pays for itself in electricity savings in a single season.
How many amps do Christmas lights draw?
A full LED residential install (200–250 ft of C9, several mini strands, and a wreath) draws about 1.3 amps on a 120-volt circuit — verified with a Kill A Watt meter in the video above. The same install in incandescent would have drawn 7–10 amps and required splitting across multiple circuits. With LED, one outlet handles the whole house.
What is the cheapest way to run my Christmas lights?
Use an outdoor timer to limit hours (4 hours/night instead of 6 cuts the bill by a third), run all-LED (no incandescent anywhere on the install), and use pro-grade gear so strands don't fail and get replaced with higher-wattage big-box stuff. A \5 outdoor timer pays for itself the first season.
Will my GFCI handle Christmas lights without tripping?
Yes. LED Christmas lights almost never trip a GFCI on load — the draw is way too low. If a GFCI is tripping, the cause is almost always water at a male/female plug connection somewhere on the run. See our GFCI tripping guide for the field fix.
About the author
Jason Geiman is the founder of Christmas Lights HQ (wholesale Christmas light supplies) and Christmas Lights University (43,000+ contractor community). He scaled a Christmas light installation business from \,000 to \M+ with four crews before selling in 2018, and now teaches the install playbook on the roof and in the classroom. Jason is a firefighter, ASE/EVT certified technician, EMT, and hazmat responder — with the electrical training that informs every number in this guide.