Matter multi-admin: one device, several apps

What multi-admin means

When you add a Matter device, your ecosystem gives it a set of credentials that let it talk securely to that ecosystem. Matter calls that a fabric. A device can hold credentials for several fabrics at once, which is the feature known as multi-admin. Google’s developer documentation explains that each fabric operates independently, and that Wi-Fi or Thread network credentials are shared by all fabrics because they belong to the device’s network settings, not to a fabric.

In practice: a lock can be in Apple Home for the family’s iPhones, in Google Home for an Android user, and in Home Assistant for automations. Home Assistant’s documentation says the standard expects devices to support at least five fabrics at the same time. Some devices accept fewer, so check the manual before planning five apps.

Before you start

• Update the device and the apps to current versions; sharing flows change between releases.
• Stay near the device with Bluetooth on. Sharing opens a short pairing window on the device.
• Know your controller’s limits. Apple says Matter accessories work without a home hub with iOS 18 or later, though it still recommends a hub, and Thread accessories need a Thread-enabled hub or a compatible border router. Confirm Thread is in place first; see the Thread border router guide.
• Find the original setup code. You will not always need it, but keep it for resets.

The order to add a device

1. Pick a primary ecosystem. Choose the app you or your household will use daily, and the one with the most complete support for that device type. Add the device there first.
2. Confirm it works from the primary app: on and off, level, status updates.
3. Open the device’s page in the primary app and look for an option such as Share, Link to another app or Pair with another ecosystem. The app generates a QR code and numeric code, which are typically valid for a short time only.
4. Open the second ecosystem’s app and choose to add a device. Scan the sharing QR code or type the sharing code. Do not scan the original sticker unless the app tells you to.
5. Repeat for each further ecosystem, generating a fresh code each time.
6. Name and room each copy. Names, rooms and automations are stored separately in each app, and they do not sync.

Home Assistant offers both directions. To bring in a device already used elsewhere, add a device, choose that it is already in use and pick the existing controller. To share out, open the device, select Share, and scan the code in the other app, with no hardware button press required. Apple’s support article says an accessory already paired with another app can be moved to a Matter-compatible app by following that app’s instructions and selecting the existing accessory.

What is shared, and what is not

One automation risk to avoid: two ecosystems both running a rule on the same device, for example Alexa turning a light off at 11 p.m. and Home Assistant turning it on at 11:05. Decide which ecosystem owns each automation.

Limits and common problems

• Device type support differs. A device can join several fabrics yet appear with fewer controls in one app. Google lists the 31 device types it supports, and Apple lists its own categories.
• The sharing code expires. If the second app cannot find the device, generate a new code and try again, keeping the phone close.
• Maximum reached. If an app refuses, remove an ecosystem you no longer use from the device’s list of fabrics. Home Assistant provides a Manage fabrics option on the device page.
• One app loses the device. See the pairing fixes.

Removing a device or an ecosystem

Apple notes that removing an accessory can mean removing it from one connected service or from all services, and that removing a service means losing control through that service’s app. Always remove the device from the ecosystem you no longer need, not just the app icon. If you sell, give away or move out, remove it from every ecosystem and then factory reset it, which clears its stored credentials. The FTC also advises disconnecting old devices you no longer use because their security may be out of date. See the moving-out smart home checklist, and switching ecosystems if you are changing platforms.