Prepositions of Time in English

Overview

Prepositions of time tell you when something happens. The three most important ones in English are at, on, in, and each is used for different types of time expressions. Choosing the right one is one of the most common challenges for English learners.

At the A1 (Beginner) level, you need these prepositions to talk about schedules, routines, plans, and everyday life. Saying the wrong preposition will not prevent people from understanding you, but learning the correct patterns early will save you trouble later.

The good news is that the rules for time prepositions are more consistent than those for place prepositions. Once you learn the patterns, they apply reliably.

How It Works

The big three: at, on, in

Preposition	Used for	Examples
at	Specific times, mealtimes, holidays (some)	at 8 o'clock, at noon, at midnight, at lunchtime, at Christmas (BrE)
on	Days, dates, specific day parts	on Monday, on July 4th, on my birthday, on Friday morning
in	Months, years, seasons, centuries, longer periods, parts of the day	in January, in 2024, in summer, in the morning, in the 21st century

General principle (from specific to general)

• at = precise moments (at 3:00, at noon)
• on = specific days (on Tuesday, on December 25th)
• in = longer periods (in March, in winter, in the evening)

No preposition

Several common time expressions do not use a preposition:

Expression	Example
this + time	I'll see you this Monday.
next + time	She arrives next week.
last + time	We met last year.
every + time	He runs every morning.
today / tomorrow / yesterday	I start tomorrow.

Special cases

Expression	Preposition	Note
in the morning	in	General part of day
on Monday morning	on	Specific day + part of day
at night	at	Exception -- not "in the night"
at the weekend (BrE)	at	British English
on the weekend (AmE)	on	American English

Examples in Context

English	Note
At 8 o'clock	Precise time
On Monday	Day of the week
In January	Month
I'll see you next week.	No preposition with "next"
The meeting is at noon.	Specific time of day
She was born on March 15th.	Date
We go on holiday in summer.	Season
I study in the evening.	Part of the day
He works on Saturdays.	Recurring day
At night, the city is quiet.	Exception -- "at" night
I started this job in 2020.	Year
Call me at lunchtime.	Mealtime

Common Mistakes

Using "in" instead of "on" for days

• Wrong: I have a meeting in Monday.
• Right: I have a meeting on Monday.
• Why: Specific days always use "on." Use "in" for months, years, and seasons.

Using "in" instead of "at" for times

• Wrong: The class starts in 9 o'clock.
• Right: The class starts at 9 o'clock.
• Why: Specific clock times always use "at."

Adding a preposition with "next/last/this/every"

• Wrong: I'll call you on next Friday.
• Right: I'll call you next Friday.
• Why: When "next," "last," "this," or "every" is used, no preposition is needed.

Using "in night" instead of "at night"

• Wrong: I can't sleep in night.
• Right: I can't sleep at night.
• Why: While we say "in the morning," "in the afternoon," and "in the evening," the word "night" takes "at." This is an exception you must memorize.

Usage Notes

The main difference between British and American English is the weekend: British English says "at the weekend" while American English says "on the weekend." Both are correct in their respective varieties.

British English also uses "at Christmas" and "at Easter," while American English tends to use "on Christmas" and "on Easter" (referring to the specific day).

In very informal speech or texting, prepositions of time are sometimes dropped: "See you Monday" instead of "See you on Monday." This is acceptable in casual contexts.

Practice Tips

• Sort your schedule: Take your weekly schedule and describe it using the correct prepositions. "I have English at 10 o'clock on Tuesday. In the evening, I go to the gym."
• Remember the size rule: Think of it as a container size. "At" is the smallest (a point in time), "on" is medium (a day), and "in" is the largest (a month, year, season). This visual metaphor helps many learners.
• Memorize the exceptions: Make a short list of the irregular cases (at night, at the weekend / on the weekend, no preposition with next/last/this/every) and review it regularly.

Related Concepts

There are no prerequisite or child concepts listed for this topic in the current batch.