につき

The expression につき is a formal written expression with two main usages: "due to / because of" and "per / for each." It is commonly seen on signs, notices, announcements, and formal documents rather than in everyday conversation.

Meaning 1: Due to / Because of / On account of

When attached to a noun that represents a reason or cause, につき means "due to" or "because of." This usage is frequently found on public notices and signs.

This usage is quite stiff and formal. In spoken Japanese, you would typically use ので or ため instead. For example, 工事のため通行止め or 雨なので中止 would be the more natural spoken equivalents.

Meaning 2: Per / For each

When attached to a noun representing a unit or quantity, につき means "per" or "for every." This is used in business contexts, pricing, rules, and regulations.

Notes

• につき is almost exclusively used in written or formal contexts – signs, announcements, business documents, and rules.
• Unlike ので or から, につき cannot be used in casual speech without sounding unnatural or humorous.
• The "reason" usage often appears with no following verb, just a short statement of the result (e.g., つうこうどめ通行止め, ちゅうし中止).