What a smart plug actually does
A smart plug sits between your wall socket and whatever you plug into it. It lets you:
- Turn the device on and off remotely via an app
- Set schedules (turn on the lamp at sunset, turn off the fan at midnight)
- Control it with voice commands via Alexa, Google Home, or Siri
- Monitor energy usage (on models with energy monitoring)
- Create automations (lamp comes on when you arrive home, heater turns off when a window opens)
What it cannot do is control a device that has its own on/off switch in the “off” position. A smart plug can restore power to a lamp, but if the lamp’s physical switch is off, it stays dark. This matters when choosing which devices to automate.
Smart plug vs smart switch: which do you need?
| Situation | Best option |
|---|---|
| Table lamp, floor lamp | Smart plug |
| Desk fan, air purifier | Smart plug |
| Window AC unit | Smart plug (check amp rating first) |
| Overhead ceiling light | Smart switch (replaces wall switch) |
| Hardwired appliances | Smart switch |
| Kettle, toaster | Smart plug (if you want scheduling) |
| Electric blanket, heated mattress pad | Smart plug (scheduling only – never leave heating unattended) |
The key rule: if it plugs in and stays physically switched on, a smart plug works. If you need to control a light that’s wired to a wall switch, you want a smart switch (like the Kasa KS200M or Lutron Caseta).
What to look for in a smart plug
Size and socket blocking: US smart plugs vary a lot in width. Some block the adjacent socket entirely. Check dimensions before buying if you’re in a double-socket location.
Energy monitoring: Not all smart plugs measure what you’re actually consuming. If you want to track running costs (useful for space heaters, wine fridges, TVs in standby), look specifically for models with energy monitoring – it’s worth the small premium.
Hub requirement: Most modern smart plugs are Wi-Fi only and connect directly to your router without a hub. A handful use Zigbee or Z-Wave and require a compatible hub. For most people, Wi-Fi is the right call.
Amp rating: Standard US sockets are rated for 13A. Most smart plugs are rated for 10A or 13A. If you’re connecting a high-draw appliance (space heater, window AC), confirm the plug can handle the load.
Protocol compatibility: If you’re building a Matter-based smart home, look for Matter-over-Wi-Fi plugs. If you’re all-in on one ecosystem (Alexa, Google, HomeKit), check compatibility before buying – most plugs support all three, but some are Amazon-only.
The best smart plugs in 2025
TP-Link Kasa EP25 – Best overall
The Kasa range has dominated the smart plug market for good reason: reliable Wi-Fi connection, a clean app, Alexa/Google/SmartThings compatibility, and energy monitoring on most models at a price that doesn’t sting.
The EP25 is the current flagship: 13A rated, energy monitoring with cost tracking, compact enough to leave the adjacent socket usable, and no hub required. Setup takes about three minutes – download the Kasa app, plug it in, follow the prompts.
The HS103 (older, no energy monitoring) is still available at a lower price point and works identically for basic on/off scheduling. If you don’t care about energy data, it’s a solid pick.
Best for: Anyone who wants a reliable plug without fussing over ecosystems. Kasa works with everything.
Avoid if: You’re building a HomeKit-first setup (Kasa doesn’t support HomeKit natively, though some models work via Homebridge).
Meross MSS110 – Best for Apple HomeKit users
Meross is the go-to brand for HomeKit compatibility at a non-Apple price. The MSS110 works natively with Siri and the Home app without any workarounds, alongside Alexa and Google Home.
It’s a straightforward plug without energy monitoring. The companion app is functional rather than polished. But for HomeKit users who want to build automations in the Apple Home app, it’s the easiest path.
Best for: iPhone households already using HomeKit for lights or thermostats.
Kasa KP115 – Best energy monitoring value
The KP115 is the dedicated energy-monitoring plug in the Kasa lineup. It tracks real-time power draw, historical consumption, and estimates monthly running costs. If you’re trying to work out whether a device is worth leaving on standby – or whether an old appliance is eating your electricity bill – this is the one to get.
It’s slightly larger than the EP25 but still leaves the adjacent socket free on most double outlets.
Best for: Tracking energy hogs – wine coolers, gaming consoles, older appliances, space heaters.
Eightree Smart Plug – Best budget option
Eightree plugs are small, reasonably well-built, and work with Alexa and Google Home. They lack energy monitoring and the app is average, but if you just want to schedule a lamp or a fan without spending much, they get the job done.
They’re often sold in 4-packs, which makes the per-unit cost excellent for fitting out multiple rooms quickly.
Best for: Scheduling non-critical devices where you just need on/off automation.
Belkin Wemo Smart Plug – Best for power users
The Wemo lineup has long been popular with home automation enthusiasts. The current Wemo Smart Plug supports HomeKit, Alexa, and Google Home, has a solid companion app with detailed scheduling, and works without a hub.
It’s pricier than Kasa or Eightree and doesn’t offer anything dramatically better for basic use. Where Wemo earns its price: robust IFTTT integration, reliable cloud independence, and a genuinely polished app.
Best for: Power users who want deep automation rules or already have Wemo devices.
Using a smart plug for your lamp
The “smart plug for a lamp” use case is the most common entry point for new smart home users, and it’s worth getting right.
What works well:
– Any standard lamp with a physical toggle switch that stays in the “on” position
– Floor lamps and table lamps where you normally leave the switch on and unplug to turn off
– Bedside lamps controlled by a schedule (auto-off at 11pm, auto-on at 6am)
What doesn’t work:
– Lamps with touch-sensitive controls or in-line cord switches in the off position – the plug cuts power, but the lamp won’t know to turn back on when power returns
– Smart bulbs in a lamp already controlled by a smart plug: this creates a conflict. Pick one or the other
Recommended setup: Use a smart plug with a lamp that has a simple toggle switch, leave the switch in the on position, and let the smart plug handle all control. Set a sunset schedule in the app and you never have to think about it again.
Smart plug for window AC: what to check first
Smart plugs can absolutely control a window air conditioner – but you need to check two things first:
Amp draw: Window AC units typically draw 5 – 15A depending on size. Check the label on the back of the unit. Your smart plug must be rated above that figure. The Kasa EP25 and KP115 are both 13A, which covers most smaller units.
Restart behaviour: When power is restored, does your AC unit switch itself back on? Many units require you to press the power button manually after a power cut. If yours does, a smart plug restart won’t turn it back on. Test this before relying on it for scheduling.
If your unit restarts automatically, a smart plug gives you genuine remote control. If it doesn’t, consider a smart AC unit or a portable unit with app control built in.
Common questions
Do smart plugs work without Wi-Fi?
No – the remote control and voice commands require an internet connection. Schedules that are stored locally on the plug will still run without Wi-Fi, but you can’t control the plug from your phone when offline.
Can two smart plugs go in the same double socket?
It depends on the model. Measure or check the product dimensions. Many Kasa and Meross plugs are designed to leave the second socket accessible; cheaper plugs often block it.
Do smart plugs use power when devices are off?
Yes – typically 1 – 2W in standby. Over a year that’s roughly $2.54 – 3 per plug. For devices where you’re saving energy by scheduling (like space heaters or old TVs), the savings far outweigh the standby draw.
What’s the difference between a smart plug and a smart extension lead?
A smart extension lead has multiple individually-controlled sockets in one unit. Useful if you want to control several devices at a desk or entertainment centre from a single device. TP-Link Kasa and Meross both make good options.
Will smart plugs work after the company goes bust?
This is a real concern. Cloud-dependent plugs stop working if the manufacturer shuts down the servers. For future-proofing, buy Matter-compatible plugs, or look at open-source compatible options (Tasmota-flashable Sonoff plugs) if you run Home Assistant.
Quick comparison
| Model | Energy monitoring | HomeKit | Amp rating | Best for |
|---|---|---|---|---|
| Kasa EP25 | Yes | No (Homebridge) | 13A | Most people |
| Kasa KP115 | Yes (detailed) | No | 13A | Energy tracking |
| Meross MSS110 | No | Yes (native) | 10A | Apple users |
| Eightree | No | No | 10A | Budget packs |
| Belkin Wemo | No | Yes | 15A | Power users |
Bottom line
For most people, the Kasa EP25 is the right call – it’s reliable, reasonably priced, works with every major ecosystem except HomeKit, and has energy monitoring. If you’re on Apple: Meross MSS110. If you want detailed energy data: Kasa KP115.
Before you buy, check that the device you want to automate stays physically switched on and restarts automatically after a power cut. If it does, a smart plug will transform it with zero wiring required.
