〜ことになっている
Formation
Meaning
Used to describe rules, customs, or schedules that have already been decided and are currently in effect.
Note
Expresses a state where a certain rule, custom, or arrangement has already been established and is ongoing. It is often used to state existing regulations, habitual family rules, or pre-established schedules. While '〜ことになる' emphasizes the point of decision, '〜ことになっている' emphasizes the resulting state or rule that currently governs a situation.
Examples
法律で、外でタバコを吸ってはいけないことになっている。
By law, one is not allowed to smoke outside.
私の家では、食後の皿洗いは父がすることになっている。
In my family, it is decided that my father does the dishes after meals.
明日の午後、先生に会うことになっています。
I am scheduled to meet the teacher tomorrow afternoon.
今度の休みは、家族で旅行に行くことになっている。
It has been decided that I will go on a trip with my family during the next holiday.
この寮では、夜11時に門限があることになっている。
In this dormitory, it is a rule that there is a curfew at 11 PM.
この会議室は、予約した人だけが使えることになっています。
It is decided that only those who have a reservation can use this conference room.