till / until

Till is just a short form of until, and in spoken English, you can use either one with no difference in meaning:

  • You can’t watch TV until you finish your homework. or You can’t watch TV till you finish your homework.
  • I’ll be in a meeting until 3:30. or I’ll be in a meeting till 3:30.

    In more formal written English, until is the preferred form – and usually when the word starts the sentence, we also prefer to use until:

  • Until you finish your homework, you can’t watch TV.
  • Till you finish your homework, you can’t watch TV.