Commission a Matter-over-Thread device into Home Assistant, with a working Thread border router. Hardware and protocol background stay in the existing threads: Matter introduction, hardware and software starter.
Complexity
Moderate. Matter commissioning is straightforward when the border router, Bluetooth, and the companion app all line up; it is frustrating when any one of those is missing.
1. You need a Thread border router
A Thread device does not join Wi-Fi. It joins a Thread mesh, and a border router connects that mesh to your IPv6 LAN so Home Assistant can reach it.
Official Home Assistant documentation describes:
- Using an existing Apple or Google Thread border router already on the LAN, or
- Running Home Assistant's own OpenThread Border Router add-on with a supported radio (for example a Silicon Labs based stick documented for that add-on).
2. Commission from the official companion app
Official docs: add Matter devices in Home Assistant with the Matter integration, typically via the companion app.
- Enable the Matter integration in Home Assistant first.
- Use the official Android or iOS companion app. Official commissioning uses Bluetooth, in part to deliver Thread credentials to the device — a desktop browser often cannot finish a Thread commission.
- Have the device's Matter QR code or numeric setup code ready, and put the device in commissioning mode as the manufacturer describes.
- Keep the phone, the border router and Home Assistant on the same logical IPv6-capable LAN during the process. Client isolation on Wi-Fi, a guest VLAN, or a missing IPv6 LAN can all stop commissioning.
- Confirm the device shows as a Matter device, with the expected entities (a bulb should dim; a plug should switch).
- Reboot Home Assistant and power-cycle the device once, to see that it returns without another QR scan.
- Only then share it with a second ecosystem if you need to. Multi-admin / sharing is official Matter behaviour, but start with one fabric working cleanly.
- A Matter-over-Wi-Fi device does not need Thread, but it still needs IPv6 and a path to Home Assistant.
- A device that is only a vendor-app product with no Matter code is not a Matter project.
- Thread radios, USB sticks and border-router hardware should be bought from a documented supplier, priced in AUD. No single public price is frozen here.
Home Assistant Matter
Home Assistant Thread
Matter introduction · Matter software starter
Researched from official documentation on 15 November 2026 (Australia/Sydney). This is a planning and how-to guide, not a claim that the exact hardware combination was assembled and tested on a live site. Please correct anything that has moved on.