You want to know what you call the date/time that something has to be submitted? (For example an assignment for school) Any of the above suggestions are fine for that situation.
学校の[課題](https://eikaiwa.dmm.com/uknow/questions/36226/)のように締め切り日のことを言うには、これらの例がぴったりです。
例：
The deadline is tomorrow.
提出[期限](https://eikaiwa.dmm.com/uknow/questions/34517/)は明日です。
When is the due date?
提出期限はいつですか？
Yesterday was the last date for submission.
昨日が最終提出期限でした。
For school assignments or a report/project at work, we use the terms Deadline and due date to state when the project/assignment must be finished.
Example sentences:
Deadline
"The deadline for the report is tomorrow at 5 pm."
"I will never be able to meet this deadline!"
"The deadline to submit your application is noon on Tuesday."
Due date
"The due date for the assignment was 2 weeks ago."
"If the project is not completed by its due date, you will be fined."
学校の宿題や会社のレポートやプロジェクトの[締め切り](https://eikaiwa.dmm.com/uknow/questions/38622/)のことを、 Deadline や due dateと言います。
例文：
Deadline
"The deadline for the report is tomorrow at 5 pm."
（レポートの締め切りは、明日の午後5時です。）
"I will never be able to meet this deadline!"
（締め切りに絶対[間に合わない](https://eikaiwa.dmm.com/uknow/questions/1173/)！）
"The deadline to submit your application is noon on Tuesday."
（申し込みの提出の締め切りは、火曜の正午です。）
Due date
"The due date for the assignment was 2 weeks ago."
（課題の締め切り日は、2週間前でした。）
"If the project is not completed by its due date, you will be fined."
（プロジェクトが締め切りまで間に合わないのなら、罰金です。）
「提出期限」は英語で、
deadline
due date
などと表現できます。
例文：
I handed in my term paper after the deadline.
締め切り期限を過ぎてからレポートを提出した。
Please submit your paper by the due date.
提出期限までにレポートを提出してください。
～ is due: 期限が来て、当然支払うべき、満期の
という英語表現もよくつかわれます。
The term paper is due tomorrow.
レポートの提出期限は明日です。
ご質問ありがとうございました。
If the request is made by email or on a website, you usually say "submit by _________. However, if it is a team project or a school project, you would say "the deadline."
リクエストがメールやウェブサイトでされたら、 "submit by"（～までに提出）と言いますが、チームのプロジェクトや学校のプロジェクトなどの場合は、締め切りのことを "the deadline."と言います。
These two words both have the same meaning with the overall idea that there is a time that something must be completed by. However in my mind, when I think of these two words I relate, "deadline," to a work/company atmosphere and, "Due date," to school/academics/homework.
Example sentences :
- The deadline for this project is next week.
- The due date of this assignment is next Friday.
これら二つの語句は同じ意味です。仕事を終わらせなければならない期限を指します。ただ私の中では、"deadline" には「仕事／会社」、"due date" には「学校／学業／宿題」というイメージがあります。
例文：
- The deadline for this project is next week.（このプロジェクトの締め切りは来週です）
- The due date of this assignment is next Friday.（この宿題の締め切りは来週の金曜です）
「提出期限」はdeadlineやdue dateと言うことができます。
例文
It's difficult to spend time with friends these days due to the deadline for my reports.
最近はレポートの提出期限に追われ、なかなか友人と過ごす時間が取れないんだよね。
deadlineの発音記号は dédlàɪn のようになり、アクセントは前に置かれる点に注意してスピーキングで使っていきましょう。
Nice questionでした！その調子で頑張っていきましょう！
Fuji
The day that a piece of work is due is called a deadline, target time, finishing time, finishing date or turn-in date.
"Please remember to have the project work in by the finishing date."
"The cut-off time for the project is tomorrow night."
"The cut-off date is tomorrow night."
締め切りのことを deadline, target time, finishing time, finishing date や turn-in dateと言います。
"Please remember to have the project work in by the finishing date."
（締め切りまでにプロジェクトを提出するのを忘れないでください。）
"The cut-off time for the project is tomorrow night."
（プロジェクトの締め切りは明日の夜です。）
"The cut-off date is tomorrow night."
（締め切り日は明日の夜です。）
The date/time that something is due can be called :-
1. Deadline
Example: The deadline for registering for this University course is 15th May.
2. Due date
Example: 17th August is the due date to complete the project.
3. Will not be accpeted beyond ..........
Example: The assignment will not be accepted beyond the 2nd November.
締切の日／時間は次のように言えます。
1. Deadline（締切）
例：
The deadline for registering for this University course is 15th May.
（この課程の登録締切は5月15日です）
2. Due date（締切）
例：
17th August is the due date to complete the project.
（このプロジェクトは8月17日までに仕上げなければならない）
3. Will not be accpeted beyond ..........
例：
The assignment will not be accepted beyond the 2nd November.
（課題の提出期限は11月2日です）
These are nouns used to express when a certain project, information or achievement is needed.
For example:
The deadline for the essay is end-of-day Friday.
The due date for your final project is March 24th.
The cut-off for submissions is after the first 150 applicants.
Note: When using the compound noun "due date" it should be followed by a specific date, such as March 24th, for example. While a "deadline" can be a time, day of the week, OR specific date.
これらは、課題・情報の提出期限や目的達成の期限を表す名詞です。
例えば：
The deadline for the essay is end-of-day Friday.（小論文の提出期限は金曜日の終業時間までです）
The due date for your final project is March 24th.（最終課題の提出期限は3月24日です）
The cut-off for submissions is after the first 150 applicants.（応募者が150名に達した時点で募集は終了いたします）
注意："due date"（複合名詞）の後には、例えば "March 24th"（3月24日）のように、日付が続きます。"deadline" の後には、日付に加えて、時間や曜日を続けることもできます。
We use "deadline" when we want to say that after this date, it is too late to submit whatever it is we must submit. This is the final date and it can't be extended, although maybe under certain circumstances it can be.
"Can I please get an extension on my paper? I understand the deadline is tomorrow but I had several other commitments that I had to take care of"
"Due date" has a similar meaning. "Due" is another way of saying "expected". This is also what we would ask a woman who is expecting a baby.
"When is your baby due?"
"Time limit" is the amount of time we have to do something. It can be used to refer to an exam or even a job that you have been asked to do.
"We have a three-hour time limit to finish this exam"
"Deadline" は、書類を提出できる最後の日を指します。それ以降は提出できないということ（例外が認められる場合もあるかもしれませんが）。
"Can I please get an extension on my paper? I understand the deadline is tomorrow but I had several other commitments that I had to take care of"
（論文の提出期限を延ばしていただけないでしょうか。明日が締切だというのは承知しています。ただ、いくつか他にやらないといけないことがあったので）
"Due date" も同じような意味です。"Due" は "Expected"（することになっている）の別の言い方です。これは妊娠した女性に対しても使います。
"When is your baby due?"（予定日はいつですか）
"Time limit" は「制限時間」のことです。これは試験や頼まれた仕事について使います。
"We have a three-hour time limit to finish this exam"（この試験の制限時間は3時間です）
If you have something that is supposed to be done by a certain time or day, it is called a "deadline".
Example:
"The deadline to submit the project is next Monday."
締め切りのことを "deadline"と言います。
例:
"The deadline to submit the project is next Monday."
（プロジェクト提出の締め切りは、来週の月曜日です。）
Submission date:
To submit something means to hand it in, so therefore
a submission date is the latest date by which you are
allowed to give something that you were working on
to your teacher, manager, boss, etc.
Cut-off time/date:
Cut-off time/date means that youare not allowed to
hand in something later than the time/date that you
were provided with, e.g. The cut-off time to hand in
your assignment is at 12 noon next Monday.
Another e.g. The cut-off is the last Friday of August.
In this case, no time has been given so you may hand
it in any time until the office/department closes.
Deadline:
A deadline is also the final time or date by when you
may submit a task, e.g. The deadline is at 5pm tomorrow.
Submission date:
"Submit" は「提出する」という意味です。ですから、"Submission date" は、上司や先生に課題を提出する期限の日を指します。
Cut-off time/date:
"Cut-off time/date" は「締切の時間／日」をいいます。
例：
The cut-off time to hand in your assignment is at 12 noon next Monday.（課題の締切は来週月曜日の正午です）
The cut-off is the last Friday of August.（締切は8月最後の金曜日です）
この場合「時間」は指定していないので、「金曜日会社が終業するまでは提出することができる」ということです。
Deadline:
"Deadline" も「締切の時間」や「締切の日」を指します。
例：
The deadline is at 5pm tomorrow.
（締切は明日の午後5時です）
I usually say deadline and think it's a more common way of saying in Britain, although, the due date can be used too. For example: " 31 of December is a deadline for all of your tasks. Please, be sure to complete all of them".
私はたいてい "Deadline" といいます、イギリスではこの表現の方が一般的だと思いますが、ただ、"Due date" も使えます。
例：
"31 of December is a deadline for all of your tasks. Please, be sure to complete all of them"
（あなたの課題は全て12月31日が締切です、それまでに終わらせるようにしてください）
If you have to submit a paper for university you will be given a deadline. This is the final date that you can submit the paper.
Example:
The deadline for this paper is Monday 22nd at 11 am.
大学に論文を提出するときには、'deadline' を与えられます。これは論文を提出できる最後の日です。
例：
The deadline for this paper is Monday 22nd at 11 am.（この論文の提出期限は22日月曜日午前11時です）
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