Sonoff MINI Duo 2 Review: A Tiny Two-Channel Zigbee Relay That Fits Where Others Can't
Two independent Zigbee relays packed into a single housing small enough for a standard switch box, with excellent Home Assistant support.
The Sonoff MINI Duo 2 solves a real installation headache: needing two smart relays in a box that only fits one. Buyers consistently praise how compact it is for a dual-channel device and how cleanly it pairs with Home Assistant over ZHA or Zigbee2MQTT, making it a favorite for retrofitting existing light switches without rewiring. It requires a Zigbee hub or coordinator to function since it has no standalone Wi-Fi connection, and it skips energy monitoring, so buyers wanting per-circuit power tracking should look elsewhere. For anyone converting traditional switches to Zigbee control while keeping the physical switch plate, it is a well-reviewed, space-saving pick.
- Retrofitting existing light switches to smart control
- Home Assistant / Zigbee2MQTT / ZHA users
- Tight switch boxes needing two relays in one unit
- DIY smart home automation
Pros
- Two independent relay channels in one compact housing
- Fits tight switch boxes where two separate relays would not
- Strong Home Assistant, ZHA, and Zigbee2MQTT compatibility
- Reliable Zigbee mesh performance reported by real installers
- Works with Google Home and Alexa
- Supports automations for scheduling and triggers
Cons
- Requires a Zigbee 3.0 hub or coordinator, no standalone Wi-Fi
- No energy monitoring
- No Apple HomeKit or Samsung SmartThings support
- Advanced per-channel behaviors can vary between ZHA and Zigbee2MQTT
Who is the Sonoff MINI Duo 2 for?
The MINI Duo 2 is built for people who want to add smart control to two separate circuits, most often two light switches, without tearing into walls or swapping switch plates. Its two independent relay channels and compact housing are designed to fit inside standard switch boxes, including tighter European 503 boxes, where fitting two separate single-channel relays would be impossible. It requires a Zigbee 3.0 hub or coordinator to operate, since it has no Wi-Fi radio of its own, so it is aimed at buyers already running or willing to run a Zigbee network such as Home Assistant with ZHA or Zigbee2MQTT.
What buyers love
The most consistent praise is for how much the MINI Duo 2 saves on space and wiring: reviewers repeatedly mention fitting it behind existing switch plates in boxes that could not accommodate two single-channel relays, matching its 2-channel design in a single compact unit. Home Assistant compatibility is another strong theme, with buyers describing smooth setup through ZHA or Zigbee2MQTT and calling the Zigbee mesh connection reliable even under network instability. Its automations support also comes through in real use cases like controlling boiler and heating demand or independently switching two separate lighting circuits from one device.
What to know before you buy
Since it only supports Zigbee (with a hub required) and has no Wi-Fi, Z-Wave, Bluetooth, or Thread radio, it only makes sense if you already have a Zigbee coordinator in place. It also does not include energy monitoring, so it cannot report power draw on the connected circuits, a limitation one reviewer specifically noted wanting. Some advanced users mention that per-channel behaviors (like independently detaching switch inputs from the relay outputs) work differently depending on whether you use ZHA or Zigbee2MQTT, so it is worth confirming your specific automation platform supports the exact mode you need. It also does not support Apple HomeKit or Samsung SmartThings directly.
Is the Sonoff MINI Duo 2 worth it?
For the specific job of adding two Zigbee-controlled relays behind an existing switch plate, the MINI Duo 2 earns strong marks from real installers, particularly in the Home Assistant community. Its combination of small size, dual relay channels, and dependable Zigbee performance makes it a practical, budget-friendly upgrade path for smart lighting and similar two-circuit automation, as long as you already have a Zigbee hub and do not need energy monitoring or non-Zigbee integrations.
Frequently asked questions
Does the Sonoff MINI Duo 2 need a hub?
Yes, it communicates over Zigbee 3.0 and requires a Zigbee hub or coordinator, such as one running Home Assistant with ZHA or Zigbee2MQTT. It has no built-in Wi-Fi.
Can the Sonoff MINI Duo 2 control two separate light switches?
Yes, it has two independent relay channels, which buyers commonly use to control two separate lighting circuits from a single compact unit fitted behind existing switches.
Does the Sonoff MINI Duo 2 have energy monitoring?
No, this model does not track power consumption.
Does the Sonoff MINI Duo 2 work with Apple HomeKit?
No, it does not support Apple HomeKit or Samsung SmartThings. It works with Google Home, Alexa, and Home Assistant.
Will the Sonoff MINI Duo 2 fit in a standard switch box?
Reviewers consistently highlight its compact size as fitting into standard and tighter switch boxes, including 503-style boxes, even though it packs two relay channels into one unit.







