以後(いご)

いご
adverb
after this, from now on, hereafter
formaltime-general
1. after this, from now on
From this point forward in time.
以後(いご)気(き)をつけます。
I'll be careful from now on.
以後(いご)このようなことがないようにします。
I will make sure this doesn't happen again.
以後(いご)注意(ちゅうい)してください。
Please be careful from now on.
2. after (a specific time/event)
Following a specified point in time or event.
3時(じ)以後(いご)は会議(かいぎ)があります。
I have a meeting after 3 o'clock.
卒業(そつぎょう)以後(いご)、会(あ)っていない。
I haven't seen them since graduation.
4月(がつ)以後(いご)に連絡(れんらく)します。
I'll contact you after April.

以後(いご) means "after" a point in time, or "from now on" when used without a preceding time reference. The boundary point itself may or may not be included.

Usage

Similar words

  • 以後(いご): after, from now on (slightly formal)
  • 以来(いらい): since, ever since (emphasizes continuation from that point)
  • 以降(いこう): from ~ onward (common in written/official contexts, includes the boundary)
  • これから: from now (conversational, neutral)

Register

Somewhat formal. In casual speech, これから or ～から後(あと) is more natural for "from now on." 以後(いご) often appears in apologies, warnings, or official instructions.

Related Words

Related: 以降(いこう) (from ~ onward (includes boundary))
Compare: 以来(いらい) (since, ever since)
Compare: これから (from now)
Compare: 今後(こんご) (from now on, hereafter)
Compare: これより (from now)
Compare: あれから (since then)
general
Added 2026.1.9 20:57 · Revised 2026.9.4 21:29
01500/01710_igo