次第です【しだいです】

次第です is a formal expression used to explain the circumstances, reasons, or sequence of events that led to the current situation. It is typically placed at the end of a sentence to wrap up an explanation, conveying the nuance of "that is why…," "those are the circumstances," or "this is how things came to be."

This grammar point is used in formal speech, business settings, presentations, and written communication such as reports and emails. It gives the listener or reader a sense of closure – the speaker has laid out the background and is now summarizing how things stand.

Explaining how a situation came about

The most common usage is to explain the process or reasoning behind a current state of affairs.

Expressing reasons or motivations

次第です can also explain why the speaker took a certain action or holds a certain view.

Nuances and usage notes

• 次第です is distinctly formal and stiff. It is not used in casual conversation. Using it in everyday speech would sound unnatural or overly pompous.
• It often appears after a clause ending in the past tense (～た次第です or ～した次第です), since the speaker is explaining events that have already occurred.
• It differs from わけです in that 次第です carries a more humble and explanatory tone, often used when addressing superiors or an audience, whereas わけです is more neutral and analytical.
• The expression しだい次第 on its own has other meanings (such as "depending on" in ～次第で), but 次第です as a sentence-ending pattern specifically functions as this explanatory closer.