cannot or can not?

People often ask me whether they should write cannot (1 word) or can not (2 words).

Cannot is a contraction of can not.

In British English cannot is the normal form.

In American English both forms are acceptable but cannot is more common.

In general I would suggest that you use cannot.

However, note that there are times when you really have to use can not. If the word “not” is part of a set phrase, then you have no choice but to use the two-word form can not. Look for example at the set phrase “not only . . . but (also)”:

  • She not only stole the money but she also lied about it.
  • He can not only play tennis brilliantly, but he can also swim like a fish.

Note, too, that cannot may be contracted to can’t, but in formal written English (such as in an essay or exam) you are not advised to use can’t.

  • Karenina says:

    More words to me.
    Thanks Josef 🙂

  • Carlos says:

    He can not only teach brilliantly, but he can also write script very well.

  • Skoon says:

    Thank you for the nice explanation. It is importnant to be attention to when we should write “can not” not “cannot”.

  • karam says:

    so nice ,, now am full knowing when i should use cannot and can not ,, thank you very much

  • Achan Malaka says:

    It is very nice knowledge. I am always asked about this case from my friends. Now, I have known it very well..Thank ya

  • sina says:

    Thank you very much indeed,Josef.

  • karoto says:

    Thanks very much, Josef

  • Silvana Ford says:

    In my country (Uruguay) in the highschool it is taught the contracted form even to be used in the tests and exams. I have a question: in the formal written, is it not correct to use other contracted forms such as “I’m”, “You’re”, “musn’t”, etc?
    Thanks very much. Your explanations are great.

  • Joe says:

    @Silvana: in general, contractions should be avoided in formal writing (eg essays, exams, business letters etc). In informal writing (eg a letter or email to a friend) contractions are normal. Bear in mind that in formal writing you might wish to quote what somebody said. If that somebody used contractions in their speech – which is almost always the case – then it is acceptable to include written contractions in the quoted direct speech, even though the overall written work is formal. It would not be acceptable to use contractions for indirect or reported speech in a formal piece of writing.

    By the way, even though “cannot” is technically a contraction of “can not”, it is acceptable in formal writing. But the “real” contraction – “can’t” – is not acceptable in formal writing.

    More about .

  • Eva says:

    Thank you Joe.

  • M.Adaway says:

    Thank you Josef for your helpful explain I cannot use can’t in my writing.

  • ye lwin says:

    I am very glad to get knowledge concerned with
    the usage of cannot and can not.
    thank you Josef,

  • Anne says:

    I used to get confusing about cannot or can’t.
    Thank you so much for explaining.

  • Andrei says:

    Thanks a lot! I heard that using “can’t” in informal speech may cause a confusing situation, because it may sound offensive, because in russian english textbooks “can’t” is pronounced [ka:nt].

  • Ameur says:

    Thank you for this wonderful explanation. I also I was wondering about this word:)

  • Deva says:

    Very nicely explained the diff of cannot & can not. We are expecting more such explanations in future

  • nada says:

    thenks very much ,, realy it’s helpful

    waiting for moreeee

  • rathanam says:

    thanks sir , i understand it ,
    sir , i am very confusion that how to use “rather” in sentence , i could not easily understand , please clear it sir

  • Hrangkil says:

    Thank you a lot Mr. Josef, it is nice explanation cannot and can not, to have me know that more rich right grammar.

  • Cyrus says:

    Thank you. You explained a confusing subject .

  • seyyed ali says:

    dear joe

    thank you for the comments and the explanations about diffrent matters

    please if you have porvide me the cds of english for today ( five vol)

    best regars

  • Jose Saul says:

    This is a very important explanation and a very helpfuk tip
    Thank you very much

  • João B. L. Ghizoni says:

    Dear Mr. Essberger,

    I greatly enjoy receiving your newsletters, and I am very thankful for them. In addition to being extremely well written, they also pass on great information for non-native speakers of English, like myself.

    I found your example of “can not” in phrases like “can not only…but also…” just fantastic!


    João, Florianópolis, SC, Brazil

  • Ed Villarreal says:

    Hey! Joe Thanks a lot, it have been very useful.

  • Yuen Mei Ha says:

    You have given very good examples to illustrate the use of cannot and can not very clearly.
    Thank you.

  • jeff says:

    Dear Josef
    I am thanking you very much
    not only for this hint
    but for your all kind helpful tips
    wish you best wishes

    Sincerely Yours

  • Arnont Arjsiri says:

    your explaination is wonderful. thanks.

  • monika says:

    Thank you Mr.Joseph for make us learn always useful hints of the English language.:)

  • Aslam Daniel says:

    Thank you Mr. Jeseph for helping us to satisfy our English improvement longing.
    Always prayful for you!

    Sincerly yours,

  • Trung Hieu says:

    Your exlanation’s very help to teachers like us. Thank you very much,Mr Jeseph.

  • Thank you very much, This kind of information is clear and we need it as teachers.

  • Thank you very much. I understood and now I can use it clearly and teach it to my students.

  • bashiir says:

    Thank u very much Mr Jeseph for ur explanation that nice and helpfull for me and I will be clued to ur explantion have a great day

  • Amiruddin says:

    Thank you very much. Now I understand

  • prudencio says:

    Very clear explanation. Thanks

  • bill says:

    Interesting how #33 can “be clued to ur …”

  • Leon mondet says:

    A new information on the use of can’t

  • hassan says:

    hi everybody
    thanks sir for this new information about cant cannot or can not……..

  • Saman says:

    Thank you very much dear Sir! I got it.

  • Aida says:

    Clear explanation. i didn’t know that ca not was also correct.

  • Rahmadi,S.Pd says:

    thank you very much! I have understood what your explaining about using cannot and can not

  • Nancy (Philippines) says:


    Thank you for unselfishly sharing
    your expertise in English language

  • sanaz says:

    thanks a lot dear sir,

  • sagor says:

    thanks a lot, Joe.
    I know it but I mistake again and again. I hope I will not do it from now

  • YEO Dogatiene says:

    Thanks a lot Joe.I did not know it.

  • Queen says:

    V.benefit I like this lesson that make our language is imroiving morer and more
    Thanks very much sir

  • Robert Li says:

    Yes,I am better from day to day. Thank you ,Professor Essberger.

  • Trainp says:

    Thank you.
    I often use “can not” instead of “cannot”.
    Now, i was knew “cannot” is common used, so i decided to use “cannot”.
    once again thank you very much.

  • David Raju says:

    Thanks Mr. josef for your contribution to English Learning and Teaching fraternity.

  • agt says:

    Thank you, now I am sure when I can use that important grammar,

  • Suro Efendi says:

    thanks, clear explaination

  • Birgit says:

    It is very, very helpful. Many thanks.

  • lucy says:

    Thanks for your helpful explanation.

  • lucy says:

    Thanks for your helpful explanation

  • Inoy says:

    Thank you so much ^_^

  • shabeer says:

    It is very helpful.thank you sir!

  • capt M.Reza says:

    Thanks for this good information,have good job,i will follow your good advises next more..
    all best

  • Anna says:

    I have got it,Thank you !

  • Eileen says:

    HI,Joe ,how about your movie about English learner?

  • Thanks its really nice 2 know the diff says:

    Thanks,its really nice of you to have revealed the difference

  • Grace says:


    Thanks Joe, your explanation is indeed very useful especially that I’m teaching English (ESL) : )

  • rana says:

    thanks alot!

  • Vega says:

    See it transcriptions, too: [kə’nät; ‘kanˌät]

  • hehe says:

    very satisfactory explanation.but there is something about rude that i do not understand.they sometimes use it like `more rude` and sometimes `ruder`.i will really be thankful if you explain that too.

  • juneth says:

    i get it! thanks a lot, joe.

  • vizimax says:

    good going

  • Arsène Reebok says:

    thanks ever much, Actually I was asked the question but I’d always answered that can not is not correct! I was mistaking now I see clearer thanks I will straightly go and tell the truth to my friends

  • Krishna S Sharma says:

    Thank you so much for sending/posting the idea regarding ‘cannot (a single word)’ or ‘can not (two words)’. And what about the tag-question when it is to be written in the negative? Don’t you think that it must be contracted?

  • mhmd says:

    I am not care about the deferent between them , becuase there is many things more important I need to know it , and the most important thing I need is leestinig ..however , thank you about any thing .. any thing is usefual for me

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