Home Assistant has shipped Matter Server 9.0 — the first general release built on matter.js instead of the previous Python Matter Server. The Home Assistant Matter integration works unchanged: it is a drop-in replacement with automatic data migration on first start.
What’s new
matter.js is an open-source TypeScript implementation of the Matter standard. After beta testing, the server was rebuilt on this stack under the Open Home Foundation. Expected gains:
- more stable Matter in Home Assistant;
- faster subsequent startups and device reconnects;
- upgrade toward the Matter 1.5.1 specification (1.6 planned);
- a stronger base for new device types (cameras, doorbells, closures, and more);
- Thread / Wi‑Fi network visualization in the web UI dashboard.
Together with an updated OpenThread Border Router (OTBR) for Thread 1.4, this is a meaningful step toward more reliable Matter in real homes.
Migration checklist
- Take a backup before updating the add-on.
- The first start can take longer — migration runs automatically; wait until logs show it finished.
- If the HA watchdog is enabled and you have many Matter nodes, disable the watchdog for the initial migration.
- The new server needs roughly 2× RAM — check free resources first.
- Later starts are usually much faster: reconnect via last-known addresses plus a partial interview.
Uncertified devices with development/test certificates can no longer be commissioned out of the box; certificate revocation data is checked during commissioning.
Project takeaway
For local installs and cloud environments such as Smarthome Cloud, plan a short maintenance window: backup, verify RAM on the mini PC / VPS, then retest key devices after migration.
Source: Home Assistant — The Matter upgrade you’ve been waiting for (June 23, 2026).
Need help updating Matter / Home Assistant — contact us.