Assumption Day on 15 August is regionally free in Germany: in Saarland and in Catholic-majority municipalities in Bavaria. Work, school, travel and opening hours therefore depend on the exact place.
In Germany, the practical effect is split: Saarland is fully covered, while Bavaria depends on the municipality.
Public holiday in Saarland and Catholic-majority municipalities in Bavaria. The decisive place is not always the home address: workplace, school location and travel destination can each change the answer.
Do not check Bavaria only; check the specific municipality. Saarland is clear, while Bavaria needs a local view of workplace, school and destination. That check should happen before booking travel, moving meetings or assuming that school and work calendars line up.