Matter over Thread devices (ALPSTUGA) not syncing time

Sat, 24 Oct 2026 22:06:42 +0200

TL;DR:

Problem: matter over thread sensor restarts (e.g. IKEA Alpstuga (ikea.com)), time is not pushed.
Cause: Matter server only pushes time updated once every 24h (source (home-assistant.io))
Solution: Matter Time Sync for Home Assistant (github.com) add-on

Installing Matter Time Sync ¶

Download into custom_components/, restart HA
Install automation

alias: '[TIME] Sync IKEA ALPSTUGA'
description: >-
 Synchronizes the time on the IKEA ALPSTUGA on Sundays at 03:15 AM and whenever
 the device becomes available after being unavailable.
triggers:
 - at: '03:15:00'
 trigger: time
 weekday:
 - sun
 - entity_id:
 - switch.kitchen_alpstuga_1
 - switch.office_alpstuga_2
 - switch.baby_room_alpstuga_3
 - switch.bedroom_alpstuga_4b_display
 - switch.bathroom_alpstuga_5_display
 from:
 - unavailable
 to: null
 trigger: state
actions:
 - delay:
 hours: 0
 minutes: 0
 seconds: 5
 milliseconds: 0
 - action: matter_time_sync.sync_all
mode: restart

Profit!

Alpstuga on Tim's blah blah blah

Matter over Thread devices (ALPSTUGA) not syncing time

Installing Matter Time Sync ¶