At/ On/ In (Time)

Compare at, on and in:

• They arrived at 5 o’clock.

• They arrived on Friday.

• They arrived in October. / They arrived in 1998.

We use:

At for the time of day

• at five o’clock, at 11.45, at midnight, at lunchtime, at sunset, etc.

On for days and dates

• on Friday / on Fridays, on 16 May 2009, on Christmas Day, on my birthday

In for longer periods (for example: months/years/seasons)

• in October, in 1998, in the 18th century, in the past

• in (the) winter, in the 1990s, in the Middle Ages, in (the) future

We use at in these expressions:

at night	I don’t like working at night.
at the weekend / at weekends	Will you be here at the weekend?
at Christmas	Do you give each other presents at Christmas?
at the moment / at present	The manager isn’t here at the moment/ at present.
at the same time	Kate and I arrived at the same time

We say:

in the morning(s)	but	on Friday morning(s)
in the afternoon(s)	but	on Sunday afternoon(s)
in the evening(s)	but	on Monday evening(s)

• I’ll see you in the morning.

• I’ll see you on Friday morning.

• Do you work in the evenings?

• Do you work on Saturday evenings?

We do not use at/on/in before last/ next/ this/ every:

• I’ll see you next Friday (not on next Friday)

• They got married last March.

In spoken English we often leave out on before days (Sunday/ Monday etc). So you can say:

• I’ll see you on Friday. or I’ll see you Friday.

• I don’t work on Monday mornings. or I don’t work Monday mornings.

In a few minutes / in six months etc.

• The train will be leaving in a few minutes. (= a few minutes from now)

• Andy has gone away. He’ll be back in a week. (= a week from now)

• They’ll be here in a moment. (= a moment from now)

You can also say: in six months’ time, in a week’s time etc.

• They’re getting married in six months’ time. or …in six months.

We also use in …. to say how long it takes to do something:

• I learned to drive in four weeks. (= it took me four weeks to learn)