Last updated: October 2026
Smart plugs are often marketed as an easy way to cut your electricity bill. The honest answer is more nuanced: a smart plug uses a little power itself, and it only saves money when it switches off something that was wasting electricity. This guide shows where the savings really come from, how to estimate them for your own home, and how to get the most out of an energy-monitoring plug.
Do Smart Plugs Actually Save Energy?
Yes, but only when they turn off devices that would otherwise waste power. A smart plug cutting a lamp you always remember to switch off saves nothing. A plug that kills standby power to an entertainment center overnight, or shuts off a fan someone forgot, can save a noticeable amount over a year.
The savings come from three habits a smart plug automates:
- Schedules: Devices run only during the hours you actually use them.
- Auto-off timers: Things like chargers, fans or holiday lights turn off after a set time.
- Remote control: You can switch off something you left on after you’ve left the house.
If you’re new to how these plugs switch power on and off, our explainer on how smart plugs work covers the basics.
How Much Power Does a Smart Plug Use Itself?
A typical Wi-Fi smart plug draws somewhere around 0.5 to 1.5 watts while idle, because its radio stays on to listen for commands. That’s a small but real cost — roughly 4 to 13 kWh per year per plug — so a smart plug only pays off when it eliminates more waste than it consumes.
This is why it makes sense to use smart plugs on devices with meaningful standby draw or long “forgotten on” periods — and not to scatter them on every outlet in the house.
What Is Phantom (Standby) Power?
Phantom power — also called standby or vampire power — is electricity a device uses while it’s “off” but still plugged in. TVs, soundbars, game consoles, set-top boxes, printers and some coffee makers keep clocks, network connections or instant-on features running around the clock, drawing power even when you’re not using them.
Individually, many modern devices draw only a few watts in standby. The problem is the combination: an entertainment center with a TV, console, soundbar and streaming box can draw a steady trickle 24 hours a day. Cutting power to that whole group with one smart plug (via a power strip) is one of the most effective uses of a smart plug for saving energy.
One caution: some devices dislike having power cut. Game consoles may need to download updates, and some TVs or set-top boxes take longer to boot. Schedule the shut-off for overnight hours, and leave Wi-Fi routers and medical devices alone.
How Do You Calculate Your Savings?
Multiply the device’s wasted watts by the hours a day the smart plug will keep it off, multiply by 365, divide by 1,000 to get kWh, then multiply by your electricity rate. Subtract the smart plug’s own standby use. An energy-monitoring plug gives you the real wattage instead of guessing.
Example: An entertainment center drawing 15 W in standby, cut off 16 hours a night:
- 15 W × 16 h = 240 Wh per day
- 240 Wh × 365 = 87.6 kWh per year
- 87.6 kWh × $0.17 = about $14.90 saved per year
- Minus the plug’s own use (~$1.50) = about $13 net savings
Your numbers will differ by device and electricity rate, which is why measuring with an energy-monitoring plug beats estimating.
Which Devices Save the Most With a Smart Plug?
The biggest savings come from devices with high standby draw or devices that are often left running by mistake. Entertainment centers, home-office setups, fans, decorative lighting and window AC units with mechanical controls are the best candidates. Low-wattage LED lamps you already switch off save very little.
| Device | Savings potential | Best smart plug feature |
|---|---|---|
| TV + console + soundbar (via strip) | High | Overnight schedule |
| Home office (monitor, speakers, printer) | Medium–High | Weekday schedule |
| Holiday / string lights | Medium | Sunset-to-midnight schedule |
| Fans left running | Medium | Auto-off timer |
| Phone and tool chargers | Low | Auto-off timer |
| LED lamps you switch off anyway | Very low | Convenience only |
How Do You Maximize Savings With Smart Plugs?
Choose a plug with energy monitoring, measure your devices for a week, and then automate the worst offenders with schedules and auto-off timers. Group several standby devices behind one plug, and use Alexa routines so everything shuts off at bedtime or when you leave home.
- Measure first: Run each device on an energy-monitoring plug for a few days to find the real power hogs.
- Use one plug per cluster: A smart plug feeding a power strip controls a whole TV or desk setup at once.
- Set auto-off timers: Ideal for fans, chargers and lights that tend to get forgotten.
- Create routines: An “Alexa, goodnight” routine can switch off everything in one command — see our guide to setting up a smart plug with Alexa.
- Don’t over-plug: Each plug uses a little power, so put them where they make a difference.
Want a plug with built-in energy tracking? Our roundup of the best smart plugs for Alexa marks which models include energy monitoring.
Frequently Asked Questions
How much money can a smart plug save per year?
It depends entirely on what it controls. A plug cutting standby power to an entertainment center overnight might save around $10 to $20 a year at typical US rates, while a plug on an LED lamp you already switch off saves almost nothing. Measuring with an energy-monitoring plug shows your real number.
Do smart plugs increase your electricity bill?
Only slightly. A Wi-Fi smart plug typically draws around one watt on standby, which costs roughly $1 to $2 a year at average rates. If it doesn’t switch off anything wasteful, that small cost is all it adds. Used on the right devices, the savings easily outweigh it.
Is energy monitoring worth paying extra for?
Yes, if saving energy is your goal. Energy monitoring shows real-time watts and monthly usage, so you can find the devices that actually waste power instead of guessing. It usually adds only a few dollars to the price of a plug and makes your schedules far more effective.
Should I put my refrigerator on a smart plug to save energy?
No. A refrigerator needs constant power to keep food safe, and switching it off can spoil food and stress the compressor. Many fridges also exceed a typical smart plug’s comfort zone at start-up. Use smart plugs for devices that can safely be off for hours, not appliances that must run continuously.
Do smart plugs save energy on phone chargers?
A little. Modern chargers draw very little power when nothing is connected, so the savings are small. A smart plug is more useful for limiting charging time on devices like e-bike or tool batteries, where an auto-off timer can prevent leaving a high-power charger running for days.
The Bottom Line
Smart plugs save energy when you point them at the right targets: standby-heavy setups, forgotten devices and anything that can safely switch off for hours. Measure first, automate second, and you’ll see real — if modest — savings. For a plug that tracks usage for you, start with our best smart plugs for Alexa guide.