Deadlines
First Thing, Close of Business, End of Day
Phrases like first thing, close of business and end of day name a position in somebody's working day, and two parties rarely have the same working day.
Who is working when, for the people on this page
Us, stating the deadline
A Friday deadline means the end of our Friday
The client reading it, Dubai
There is no working Friday in their week at all
two parties · four days of the seven are working days for all of them · Mon, Tue, Wed, Thu
The phrase that started this was 'by Friday'. It felt complete to the person who wrote it, which is the whole of the difficulty.
Before moving another call into somebody's evening, it helps to review the platform and check how the work is actually distributed across projects and days.
For a separate reference on calendars, standards, or international operations, consult Harvard Business Review.
Five office phrases, and the instant each side attached to them
“First thing Monday”
You: Mon 09:00 · Them: Mon 02:00 — Their first thing is seven hours before ours, and the file was already waiting
“Close of business Thursday”
You: Thu 17:00 · Them: Thu 23:00 — Their close of business is six hours after ours and is still the same day
“End of day”
You: Wed 18:00 · Them: Wed 13:00 — Said by somebody five hours ahead, so the day ended at lunchtime here
“Before you go home”
You: Fri 17:30 · Them: Fri 10:30 — A sentence with no fixed meaning even inside one office
“Overnight”
You: Tue 08:00 · Them: Mon 20:00 — Their overnight is our afternoon, so the work happened while we were at our desks
five phrases · every one read as two different instants · the widest gap between the two readings is 12 hours
Every one of these is a phrase about somebody's working day rather than about a time. They work perfectly inside one office and nowhere else. One team's own job.
"First thing", "close of business", "end of day", "overnight", "before you go home" — all of these are positions in a working day rather than times, and they are exact only to people who share the day.
They are also the most natural way to talk about short deadlines, which is why they persist long after they have stopped being accurate.
What each one actually means
The phrase names an edge of somebody's day. Which edge, and whose day, determines the instant.
| Phrase | What it names | Where it goes wrong |
|---|---|---|
| First thing | The start of the recipient's day | Which may be the middle of the sender's night, or already past |
| Close of business | The end of the recipient's day | Different by up to several hours, and on a different day if the week differs |
| End of day | Ambiguous between sender's and recipient's | The most frequently misread of the five |
| Overnight | The sender's night | Which is somebody else's working afternoon |
| Before you go home | The recipient's departure | Which is not a fixed time even for one person |
Why they are not simply replaced
Because they carry information a timestamp does not.
"First thing Monday" says: this is the first thing I want you to do, and it does not matter whether that is at eight or at ten. "Close of business" says: any time today is fine, I will look at it tomorrow. "Overnight" says: I am not waiting for this, do it when it suits.
Replacing those with "by 09:00 UTC" removes the ambiguity and also removes the message about priority and tolerance. A deadline that is less precise than the speaker's actual requirement is often doing useful work.
The form that keeps both
State the instant and the tolerance together, which takes one more clause.
Any time before your close of business on Thursday — I will pick it up on Friday morning my time, so there is no need to rush it.
That gives the recipient the edge of their own day, which is what they can act on, and tells them what the real constraint is, which is what lets them judge whether a two-hour slip matters.
"Overnight" is the one to retire
Of the five, this is the one that does genuine damage, because it is usually said by the party with more power in the relationship and it describes a night that belongs to somebody else.
"Can you look at this overnight" said to a counterparty eight hours behind means: do this during your working afternoon. Said to one eight hours ahead it means: do this during your evening. The sentence is identical and so is the speaker's intention, and the two recipients receive very different requests.
Where the overlap is large enough that somebody's night really is involved, the word is doing the opposite of what it looks like: it is asking for unpaid out-of-hours work in a tone that makes it hard to refuse, because no specific hour has been named and therefore nothing unreasonable has been asked.
The reply that fixes it
When one of these arrives and the answer matters, reply with the instant you have understood.
Close of business Thursday — I will have it to you by 16:00 your time, which is 11:00 here.
Two numbers, one line, and the ambiguity is gone without anybody having had to say that the original was unclear. The other party can correct it in four words if it was wrong.
What to do inside your own messages
Keep the phrases for the cases where the tolerance is what matters and nothing turns on the exact hour.
Drop them entirely where money, a cut-off or a third party's commitment depends on the date. That is a small set, it is identifiable in advance, and in that set the loss of warmth from writing a timestamp is not a real cost.
The test is simple: if the thing arriving four hours later than you meant would require a conversation, the phrase is doing too much work and should be a time.
The phrases that travel
Not all of them fail. A few carry across a border intact and are worth keeping.
"When you get a moment" is honest about having no deadline and is understood everywhere.
"Before the end of the week" is vague in a useful way: it names a boundary that both sides can compute on their own calendar and tolerates a day either way.
"Whenever suits you" means what it says, and in a relationship where somebody is doing you a favour it is the right phrase.
What they have in common is that none of them is pretending to be precise. The failures in this part of the subject come from phrases that feel exact to the writer and turn out to be approximate; phrases that are openly approximate cause very little trouble, because nobody plans against them.