TP-Link Kasa KS240 Smart Double Switch for Dual Load Control

The Kasa KS240 Smart Double Switch fits a single gang box yet controls two separate lighting circuits. At $34, it's one of the few Wi-Fi switches that lets you run independent loads from one wall plate without any hub. We installed it in a hallway with separate overhead lights and a sconce - two circuits that previously needed two gang boxes. Setup took about 20 minutes from first screw to first voice command.

What Makes the KS240 Different from a Standard Smart Switch?

Most smart switches control one load. The KS240 has two independent rockers on a single plate, each tied to its own circuit. You can dim or toggle load one without touching load two. That's genuinely useful in rooms where a ceiling fixture and accent lighting share a wall location but need separate control. No adapter, no second gang box, no extra switch to wire in.

Hardware Overview

The KS240 runs on 2.4 GHz Wi-Fi using the 802.11 b/g/n standard. It does not support 5 GHz. Both circuits share the same Wi-Fi radio, so they appear as two separate devices inside the Kasa app. A neutral wire is required on most home wiring setups. Older homes wired before the mid-1980s often lack a neutral at the switch box, which means the KS240 won't work in those locations without a rewire.

Rated specs from TP-Link's product page list each rocker at up to 300 watts for incandescent or halogen loads and 150 watts for LEDs. That covers most residential fixtures. The unit carries FCC and ETL marks - ETL listing means it has been independently tested to UL safety standards for North America.

Does the Kasa App Actually Work?

Short answer: yes, and it's fast. The Kasa app on both iOS and Android recognized the switch as two separate devices during our test. Each device gets its own name, schedule, and scene assignment. Response time from tap to relay click averaged under one second on a home network with moderate traffic. The app also supports energy monitoring on some Kasa devices, but the KS240 does not include that feature - you won't see wattage readings.

Schedules sync to the cloud, so programmed timers survive router reboots. The away mode feature randomly toggles each circuit on and off to simulate occupancy. It's a basic security feature, but it works reliably in practice.

Voice Assistant Compatibility

The KS240 works with Amazon Alexa and Google Assistant out of the box. Link your Kasa account in either assistant's app and both circuits appear as individual smart home devices. Siri Shortcuts via the Kasa app allow iOS users to trigger the switch through the Shortcuts app, though it doesn't appear as a native HomeKit device. Apple HomeKit is not natively supported on the KS240.

Home Assistant users can poll the KS240 locally using the TP-Link Smart Home integration, which works without cloud access once the device is on your network. Local polling means your schedules and automations keep running even if Kasa's cloud servers go down.

Setting Up the KS240

The physical install follows standard smart switch wiring:

• Turn off the circuit breaker for both circuits before touching any wires
• Connect line (black), two separate load wires, neutral (white bundle), and ground
• The KS240 ships with a wiring diagram and wire-identification stickers
• Restore power and hold the reset button until the LED blinks rapidly
• Open the Kasa app, tap the plus icon, and follow the 2.4 GHz pairing flow

The pairing process took about three minutes in our test. The app walks you through naming each rocker and assigning rooms. Total time from box to working: roughly 20 minutes if you're comfortable with basic electrical work. If you've never wired a switch before, hire an electrician - working inside a live panel is not a beginner task even when the breaker is off.

One Gotcha Worth Knowing

Both loads share a single line terminal on the KS240. If your two circuits come from different breakers, you can't install this switch - both loads must share the same hot line. Check your wiring before purchasing. Most single-location multi-circuit installs do share a line, but it's worth confirming before you open the box.

Who Should Buy the Kasa KS240?

The KS240 makes sense if you have two circuits in one gang location and want independent smart control without running a second gang box. The $34 price is competitive - two separate smart switches of similar quality would cost more and require a wider wall plate or a second box.

It's not the right pick if your home lacks a neutral wire at the switch location, if you need native Apple HomeKit support, or if you want energy monitoring on a per-circuit basis. For those cases, look at Lutron Caseta or the Leviton Decora Smart line.

In everyday use the KS240 delivers what it promises. The app is responsive, voice control works without lag, and the dual-rocker design keeps the wall plate clean. It's a practical upgrade for any room where two circuits meet at one wall location.

The KS240 also fits well into existing Kasa ecosystems. If you already run Kasa plugs or other Kasa switches, both circuits appear alongside your other devices in the same app view. Groups and scenes work across the full Kasa lineup, so you can include the KS240 circuits in a "Goodnight" scene that powers down lights across the house at once.