Third Reality Smart Plug E3 Review: A Compact Zigbee Meter for the Whole Home
The Third Reality Smart Plug E3 is an EU Type F Zigbee 3.0 plug built around energy metering: it reports power, voltage, current, power factor and accumulated energy in real time, and doubles as a Zigbee router. It is a sound choice for a Home Assistant, SmartThings or Alexa household that already has a Zigbee coordinator, while anyone without one will need a hub first. At a budget-friendly price it is one of the cheaper ways to add metering to an existing Zigbee mesh.
- Home Assistant and Zigbee2MQTT users
- SmartThings and Alexa households
- Energy monitoring on a budget
- Extending an existing Zigbee mesh
Pros
- Real-time power, voltage, current and energy metering calibrated to about one percent
- 16 A and 3680 W capacity on a 100 to 250 V supply
- Works as a Zigbee router to extend the mesh
- Local control over Zigbee with no cloud account
- Physical on/off button and configurable power-on state
- Compact 55 mm Type F body
Cons
- Needs a Zigbee hub or coordinator, with no Wi-Fi, Bluetooth, Z-Wave or Thread radio
- Apple Home, Google Home and Matter only through the Smart Bridge MZ1, sold separately
- No overcurrent or overheat cut-off listed in the manual
- No IP rating, so indoor use only
- No USB charging port
Who is the Third Reality Smart Plug E3 for?
The E3 suits a home that already speaks Zigbee. It pairs with a Zigbee coordinator such as an Echo 4th Gen or Echo Plus, a SmartThings 2015/2018 hub, an Aeotec Smart Home Hub, Hubitat, Homey, a Home Assistant setup running ZHA or Zigbee2MQTT, or Third Reality's own hub and Smart Bridge. Because the plug is powered all the time, it also works as a router that extends the mesh for other Zigbee devices. The 16 A rating and 3680 W maximum load cover most household appliances, and the 55 mm body is compact enough for a standard wall outlet.
What the Third Reality Smart Plug E3 offers
The headline feature is metering: the plug exposes power, voltage, current, AC frequency, power factor and total energy, with Third Reality claiming factory calibration to about one percent. Zigbee2MQTT and ZHA also expose power-rise and power-drop thresholds, so an automation can react the moment a washing machine or a fridge changes state. A physical button toggles the relay by hand, the plug remembers its on or off state after a power cut on supported platforms, and it can run in a metering-only mode that keeps the relay on. Firmware updates arrive over the air without switching the relay off. The plug is white, uses the EU Type F socket, and works over the 100 to 250 V range.
What to know before you buy
This is a Zigbee end device, not a Wi-Fi plug: it needs a Zigbee coordinator before it can be used at all, and it has no Wi-Fi, Bluetooth, Z-Wave or Thread radio of its own. Apple Home, Google Home and Matter are reachable only through Third Reality's Smart Bridge MZ1, sold separately, which republishes the plug over Matter; Alexa and SmartThings work directly through their own Zigbee hubs. The manual lists zero-cross switching and a configurable power-on state but no overcurrent or overheat cut-off, so an automation that watches power is the safety layer here. There is no IP rating, which means indoor use only, and no USB charging port.
Is the Third Reality Smart Plug E3 worth it?
For a Zigbee household the E3 packs the three things that matter into one small plug: accurate metering, a physical button with local control, and a repeater that strengthens the network. It is a budget-friendly alternative to metering plugs that cost considerably more, and its Type F format fits most European outlets. The trade-off is the hub requirement and the indirect route to Apple Home and Google Home. If you are already running Zigbee, it is an easy recommendation; if you are starting from scratch, budget for a coordinator as well.
Frequently asked questions
Does the Third Reality Smart Plug E3 need a hub?
Yes. It is a Zigbee 3.0 end device and needs a Zigbee coordinator, such as an Echo 4th Gen or Echo Plus, a SmartThings 2015/2018 hub, an Aeotec Smart Home Hub, Hubitat, Homey, a Home Assistant setup with ZHA or Zigbee2MQTT, or a Third Reality hub.
Does it work with Home Assistant?
Yes. Third Reality documents both ZHA and Zigbee2MQTT, and Zigbee2MQTT lists a converter for this exact model with switch, power, voltage, current, energy, power factor and AC frequency entities.
Does it monitor energy consumption?
Yes. It reports real-time power, voltage, current, power factor and total energy, and Third Reality states the meter is factory calibrated to about one percent.
Does it work with Apple Home, Google Home or Matter?
Only through Third Reality's Smart Bridge MZ1, sold separately, which republishes the Zigbee plug over Matter. The plug itself is not a Matter or HomeKit device.
What is the maximum load?
It is rated at 16 A and up to 3680 W on a 100 to 250 V supply, which covers most household appliances.
Does it extend the Zigbee network?
Yes. Because it stays powered, the E3 acts as a Zigbee router and repeats the signal for other Zigbee devices in the mesh.




