There are lots of smart home products that work with Apple's HomeKit interface, which makes secure setup a breeze and allows you to control everything from the Home app on your iPhone. But as many products as there are, there's not enough to control every lamp and small appliance you want to.
That's where smart plugs come in. Plug one into your regular wall outlet, then plug your dumb device into it: a lamp, a fan, an electric kettle, whatever. If the smart plug supports HomeKit, you can then use the Home app or Siri (not to mention Shortcuts) to effectively turn that outlet on or off.
To really make the most of a HomeKit-compatible device, you'll want to make sure you've got either an Apple TV, HomePod, or plugged-in iPad on your local network at home to act as a Home Hub. This will allow you to control your HomeKit accessories remotely and even set up Automations that control several devices at once based on time, location, or the actions of other devices.
Our sister site TechHive reviews lots of smart plugs, but if you're into the Apple ecosystem, you may not care much about those that only support Alexa or Google Assistant; you probably want one that works with HomeKit (in addition to its own app features). These are the top rated smart plugs that are compatible with HomeKit.
Updated 01/18/22: We've updated our list with some newer choices as reviewed by our smart home sister site TechHive.
Best smart plug for most people
Leviton continues to make our favorite smart plug, and its second-generation device—model D215P—adds HomeKit compatibility to its repertoire (the plug supports Alexa and Google Home, too). Like its predecessor, this smart plug connects directly to your network over Wi-Fi, so you don't need to invest in a hub. And its slim form factor means you can plug two of them into the same duplex outlet. This is an on/off device, not a dimmer. If you need dimming functions, consider Leviton's second-gen Decora Smart Mini Plug-In Dimmer (model D23LP).
Best smart plug for power users
The hub in Lutron's starter kit can control more than just the smart plugs that come with it. It also supports Lutron's in-wall dimmer switches and Serena powered window shades. All this stuff works with HomeKit, as well as other smart home ecosystems.
The downside is that these are two-prong plugs that convert a regular plug into a dimmer switch, and as such are only to be used with lamps. If you want to control a fan, heater, or electric kettle, for instance, you need a straight on/off three-prong plug instead.
Other HomeKit-compatible smart plug reviews
ConnectSense Smart Outlet 2
Lutron Caséta Wireless Smart Lighting Lamp Dimmer Starter Kit (Model P-BDG-PKG2P)
Legrand Smart Plug-In Universal Dimmer (model HKRP20 )
Meross Smart WiFi Plug (model MSS120HK)
Wemo WiFi Smart Outdoor Plug