Do you say I´ll arrive in the first week of July? or on the first week of July?


6 Answers 6


You arrive in the first week of July...on a jet plane.

You arrive on July 4th...in a jet plane.

For month/week, use the preposition "in." For specific dates, use the preposition "on."

  • 4
    Why use "on a jet plane" in the 1st sentence and "in a jet plane" to the 2nd?
    – Dreamer
    May 28, 2014 at 17:45

It is also acceptable to use no preposition whatsoever:

I'll arrive the first week of July

This is also acceptable with specific days

I'll arrive July 5th

This does not work with specific years.

I'll arrive in 2014. (only 'in' works)

However you can say

I'll arrive next year. ('in' would be incorrect here.)


Neither. I would say:

I´ll arrive during the first week of July.


The preposition 'in' is used with parts of the day, months, years, seasons etc. Whereas 'on' is used with days and dates.

So for the question asked, 'I'll arrive in the first week of July.' is the appropriate answer.


'IN' is used with:

  • parts of the day (in the morning, in the afternoon, in the evening; note the exception: at night)
  • longer periods of time - weeks (in the 1st week of July), months (in July, in July 1969), years (in 2014), centuries (in the 15th c.)
  • seasons (in winter)

'ON' is used with:

  • weekdays (on Monday)
  • dates where the day of the month or another sequential number is given (on the 5th, on July 4th, on day 12)
  • events - both astronomical (on an eclipse) and human (on my birthday, on Independence Day)
  • parts of the day, when they are described somehow (on Monday morning, on some afternoons, on a cold winter night)
  • weeks, when more than one occurred during a set amount of time - typically followed by a/an (on a cold week in July)
  • weekends in AmE (on the weekend)

'AT' is used with:

  • "at night" (an exception)
  • exact times (at 5 o'clock)
  • longer-than-one-day holidays (at Christmas, but on Christmas Eve)
  • weekends in BrE (at the weekend)

nothing is used with:

  • next/last/etc followed by any of the above (weekday,week,...,year,century), when used without the 'the' article ('I arrived last week', 'I'll be there next Tuesday', etc.)

In your case, since you're using "first week", you need "in": "I'll arrive in the first week of July."'


I would either use "on" - or NO preposition, which I think is more natural.