How to say "formerly" in Japanese

• かつてJLPT N1approx.Common
  adverb, no-adjectiveThe usual adverb for 'once, formerly', normally written in kana: it presents something as true in the past, typically implying things are different now. Good for a former state, role, or era.
  一般いっぱんに日本人にほんじんは、自分じぶんたちがかつてより暮らし向くらしむきがよくなったと考かんがえている。↗

  The Japanese at large consider themselves better off than they used to be.
• 旧来きゅうらいCommon
  no-adjective, adverbChiefly means 'traditional, long-established', so it fits 'formerly' only loosely; seldom the word for a plain 'it was formerly X', it instead labels customs, methods, or ideas as old-established.
• 先年せんねんCommon
  noun, adverbPoints to a specific, fairly recent past — 'a few years ago' or 'in former years' — rather than an indefinite distant era. Use it when 'formerly' really means 'some years back'.
• 先にさきにJLPT N1approx.Common
  adverbReally means 'earlier, before, previously' relative to another point in time; its 'formerly' gloss covers cases where you simply mean something happened before something else, not a distant 'once'.
• 一時いちじJLPT N3approx.Common
  adverb, nounCovers 'at one time, for a while': it frames something as holding during a certain period in the past, often a temporary phase, rather than characterizing it as former overall.
  彼かれは一時いちじここに住すんでいた。↗

  He lived here for a time.

Choose 「かつて」 for 'once, no longer true', 一時 for 'at one time, for a while', 「先に」 for plain 'earlier', 先年 for 'a few years ago', and treat 旧来 as 'traditional' rather than a true 'formerly'.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• かつてonce
• 旧来きゅうらいtraditional
• 先年せんねんformer years
• 先にさきにpreviously
• 古くふるくanciently
• 先にせんにformerly
• 一時いちじonce
• 元もとformerly