I don't know exactly when we'll go but we really must visit them one of these / one of those days.

When should we use "one of these days" and "one of those days"?

6 Answers 6


One of these days

One of those days

These are idioms.

The former means sometime in the near future. So you can say "we really must visit them one of these days".

The latter (one of those days) means a bad day; a day when everything goes wrong.

I missed breakfast, got late to work, and got caught in the rain at lunchtime - it was one of those days! (The Free Dictionary).

It looks like it's going to be one of those days (McMillan).

So you shouldn't use this idiom in your sentence presented.

  • 9
    Not always. I don't know exactly when we'll go but we really must visit them one of those days [that we talked about last week]. This has no meaning of a bad day. The usage is similar to I saw one of those dogs back in the yard again. Both (one of) those days and (one of) those dogs refer to things that are familiar. In fact, this is where the idiomatic usage of a bad day comes from. Have you ever had one of those days, you know, the kind where everything goes wrong? Commented Jun 7, 2016 at 16:31
  • 7
    It should be added that the "one of these days" idiom implies a lack of strong will to actually chose a day and do the stated thing. It's something you don't want to do (go to the gym), or want to do but know realistically you probably won't (have coffee with an old friend who is also really busy).
    – mattdm
    Commented Jun 8, 2016 at 2:44
  • 2
    Obviously overall correct, but I would dispute the definition of one of these days as "sometime in the near future." I'd say it means "sometime in the future, maybe" (e.g., not "near," and much more conditional than "sometime in the near future" -- frequently it's never going to happen, and the speaker knows that even when saying it). Commented Jun 8, 2016 at 12:20
  • 2
    @AlanCarmack Do you have a citation for that? I've never seen "those days" used , at least by anyone literate, in that way. Commented Jun 8, 2016 at 12:58
  • 7
    @CarlWitthoft I can easily imagine a conversation like this "When should we have lunch? Next week I'm free on Tuesday, Wednesday, and Friday, so it will have to be one of those days." That said, I think that's a direct usage of those words, and not the idiom "one of those days". The intonation in my example and in "It's going to be one of those days..." is very different. Commented Jun 8, 2016 at 14:11

The short answer.
The two phrases are idioms.

  1. one of these days
    On some day in the future
  2. one of those days
    a day when everything goes wrong

So if you want to visit them in the near future, but you're not sure when, then use

I don't know exactly when we'll go but we really must visit them one of these days.

The long answer.

The two expression have them meanings as above, but they can also take on various meanings depending on the context.

For example "one of these days" can also mean

[1.] someday; in some situation like this one
One of these days, someone is going to steal your purse if you don't take better care of it. You're going to get in trouble one of these days.

It can also be used to refer to the past. For example, if you are looking at a calendar from last year, you started point at the month of May. As you tried to recall a particular event, you say "I know it happened one of these days, but I can't remember which one."

As for "One of those days", it can also used when referring to specific days or dates, in the future or in the past.

For example,

  1. During the last week of June, one of those days I will mail this letter.
  2. Back in high school, I remember one of those days I have quite a terrific day.

Finally, if you're looking ahead in a calendar, for example, and you know that on certain days the weather will be favorable, you could say

I don't know exactly when we'll go but we really must visit them one of those days.

  • 2
    It's reasonably clear what your "last week of June" and "back in high school" examples mean, but they don't read well. Nobody would say "one of those days" to refer to years at high school - they might say "in those days". It's not grammatically correct to say "Back in high school...I have", it should be had.
    – nnnnnn
    Commented Jun 8, 2016 at 6:08
  • I made a typo in number 2, but other than that, how are they grammatically incorrect?
    – Em.
    Commented Jun 8, 2016 at 6:11
  • I see. However, nobody would say that? I don't think that is a fact. I would say that.
    – Em.
    Commented Jun 8, 2016 at 6:15
  • Sorry, just saw your comments after editing my comment. Perhaps not literally nobody, but I can say that I've not previously heard that wording. Most people would say "I will mail this letter during the last week of June", they wouldn't say "During the last week of June" and then immediately use "one of those days" to refer back to what they just said.
    – nnnnnn
    Commented Jun 8, 2016 at 6:17
  • I understand what you are saying, but "most people" is not all people. In other words, it is feasible that it could be said. You could think about it, and reassure yourself of when you're going to mail it. Thus immediately referring back to it.
    – Em.
    Commented Jun 8, 2016 at 6:23

you should use

One of THESE days

because these signifies upcoming events, that are in the future, while those signifies past events. for eg :

One of THESE days I'm going to the gym.

This signifies that I am planning to go to a gym in the upcoming days, whereas

THOSE were the days when I used to go to the gym.

This sentence states that I am remembering past events , like I remember going to the gym

so, saying that

I don't know exactly when we'll go, but we really must visit them one of these days.

means that you are planning to go visit someone in the upcoming days.

  • 7
    One of those days is also used in a negative way to indicate a bad day. I'm having one of those days today
    – PerryW
    Commented Jun 7, 2016 at 10:29
  • 3
    "Those were the days" is an unrelated idiom that refers to a past event with a positive connotation. There aren't any rules with idioms (those vs these); that's what makes them idiomatic. Commented Jun 7, 2016 at 21:24

When you will do something at a future date you say "one of these days".
e.g. "One of these days Alice, Bam! Right to the moon!".

When you will refer to, typically a bad day, you say "one of those days".
e.g. "I tripped and fell into a mud puddle; today is one of those days."


Both can be used in a purely literal sense for example.

'Any one of these days would be suitable for a meeting: 2nd January, 24th January or 1st February.'

'I am definitely busy on one of those days but I will be free for at least one, I will let you know.'

However, in isolation both phrases do have specific additional meanings.

'One of those days', generally means a bad day. as in 'Sorry if I'm in a bad mood I've just had one of those days'. Here it is given addition meaning by inflection and/or context.

However if can be positive if qualified 'It was one of those days where everything falls into place'.

In both cases there is an implication that it is a state of affairs that both parties will be familiar with.

'One of these days', can be used to indicate an intention to do something or a belief that something will happen at some indeterminate time in the future, eg. :

'One of these days I will get around to fixing that leak'.

'He will get into serious trouble one of these days'.

In general terms 'these' implies something immediate or close to hand eg.

'Would you like to try any of these apples?'

Whereas 'those' implies something a bit more distant or removed from the speaker eg.

'Those hills are a nice place for a walk'.


Most of you seem lost if not completely incorrect. The usage is not idiomatic, and, contrary to what some said, there is nothing inherently negative about those.

First, these and those: These two words are plural demonstrative pronouns, and the meaning distinguishing the two has to do with proximity. These is used to refer to things relatively close; those is used to refer to things relatively distant. The context resolves the relativity of the two words. These words serve for both time and space.

Simply put, the use of those days, as opposed to these days (implicit or explicit), refers to a period that isn't now. It can be in either the past or the future.

For example, the song "Those Were the Days" (an old song from the 1920s, made a hit again by Mary Hopkin under Paul McCartney's production) refers to a good time in youth:

Those were the days my friend
We thought they'd never end
We'd sing and dance forever and a day
We'd live the life we choose
We'd fight and never lose
For we were young and sure to have our way.
—Those Were the Days.

As you can see, there is nothing inherently negative in those: it just mean days that are not now, not these days. You can also speak about those days that lie ahead:

Those days will be much brighter.

That, which is the singular form of those, is often paired with day to refer to the dies irae, judgment day or, literally, the day of anger. It comes up in Ingmar Bergman's The Seventh Seal in this exchange between the Knight (Max von Sydow) and Death (Bengt Ekerot):

But one day they will have to stand at that last moment of life and look towards the darkness.

When that day comes ...
—The Seventh Seal. (emphasis mine)

It is common in the literature that speaks of the day of reckoning to refer to it simply as that day because of fear of the day, rather like in the Harry Potter series Voldemort is more commonly referred to as He-Who-Must-Not-Be-Named.

So to the OP's question:

When should we use "one of these days" and "one of those days"?

It is a judgment call, but that judgment should depend upon whether the day that you are talking about belongs more to the period that you are in, or the period that you will be in (or were in), and the sense of proximity is drawn from the context of the conversation.


He was starving, had no money at all, so he looked forward to drawing Social Security because when those days arrive he will be able to eat a little something.

[In those days] We used to have plenty of food, but these days the pantry is bare.

My rickety old grandfather is a standup comedian. In those days when he used to tour constantly, we never saw him. But these days he keeps us laughing constantly.

My daddy used to say that one day America will have to face a terrible reckoning. Judging from the progress of the electoral campaigns, those days may be hard upon us.

  • 2
    OP asked about 'one of those/these days'. Both 'one of those days' and 'one of these days' absolutely is idiomatic. As an idiom, the those in 'one of those days' absolutely is referring to negativity. Your examples are also somewhat contrived: in the first: 'because when that day arrives'; the third: 'In the days' (arguably if the conversation was referring to previous days in earlier sentences, your choice would be used, but without context 'the' is more natural and in the fourth: 'one day ... electoral campaigns, that day may be hard upon us.
    – mcalex
    Commented Jun 8, 2016 at 4:34
  • "Those dogs" refer to dogs that are somehow alien, remote. Possibly they're not of the neighborhood. Yes, the proximity issue can be used to distinguish things of greater or lesser familiarity, but those is somehow more distant than these: that's the meaning of the word. A speaker would be more familiar with "these dogs" than with "those dogs." If this week comprises "those days I told you about," it implies that what was distant when I brought it up has now arrived. "Those [days] were the days" is a positive statement in the example that I provided, so mcalex is wrong. Commented Jun 8, 2016 at 4:43
  • The specific wording "one of those days" is an extremely well known idiom describing a bad day. Your attempt to provide a counter example that is a positive statement uses a different wording, "those were the days", which is another well known idiom. In any case, the fact that "one of those days" is a well known idiom in no way prevents the same words being used in other contexts, for example "The doctor only works Tuesdays and Fridays, so you'll have to make an appointment on one of those days." The question didn't ask about "those days", it asked about "one of those days".
    – nnnnnn
    Commented Jun 8, 2016 at 6:24
  • 3
    You went through a lot of trouble writing a very lengthy piece of text about all kinds of ways to use these and those in combination with day or days, but you utterly failed to recognize the specific usage the OP asked about, and thus you completely failed to actually answer the question, unlike the people you accuse of being "lost".
    – oerkelens
    Commented Jun 8, 2016 at 12:39

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .