Direct answer
Use the first ecosystem's multi-admin or sharing flow to generate a fresh setup code for the second ecosystem. The code printed on the device may not be the correct code after commissioning.
What this covers
- A Matter device and two ecosystems that both support that device type and Matter version
- The exact condition described in the direct answer
- Customer-accessible observations and controls
What it does not cover
- ×A different model, region or software interface that contradicts the cited source
- ×A displayed code with a separate manufacturer meaning
- ×Live electrical, gas, sealed-system or battery-cell repair
Establish the exact starting state
ReversibleConfirm a working primary fabric, compatible hub/controller, same local network and administrator access in both ecosystems.
Separate the fault or decision boundary
ReversibleCheck device-type support and Thread-border-router requirements in the destination ecosystem before removing anything.
Apply the narrowest correction
ReversibleOpen the primary ecosystem's sharing or multi-admin flow and enter the newly generated code in the destination app.
Verify before escalating
ReversibleControl the device from both ecosystems and test automations without deleting it from the first.
Evidence ledger
Sources behind this answer
Visible sources support the visible claims. Home Product Support records the publisher, the fact used and the review date; community reports can suggest an issue but do not become a published fact on their own.
Exact questions
Common follow-ups
What is the short answer to “Add one Matter device to a second smart-home ecosystem”?+
Use the first ecosystem's multi-admin or sharing flow to generate a fresh setup code for the second ecosystem. The code printed on the device may not be the correct code after commissioning.
What should I check before changing anything?+
Confirm a working primary fabric, compatible hub/controller, same local network and administrator access in both ecosystems.
How do I know the action worked?+
Control the device from both ecosystems and test automations without deleting it from the first.
When should I stop?+
Removing or factory-resetting the accessory can break the working fabric and require physical recommissioning.
Answer for the exact device and software version shown above.