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“That” vs “Which”

People often ask about the difference between that and which. Where should each word be used? What’s the difference between them?

It can be a tricky question. That’s because the distinction between that and which can be very subtle. Here’s the short answer to the question of that and which:

That usually introduces essential information in what is called a “restrictive clause.” Which introduces extra information in a “nonrestrictive clause.”


  • I am offering a new class, Email Intelligence, that/which may be an excellent fit for your training needs and budget.

Does the clause (in red) introduce information that is essential to knowing which Email Intelligence class?

No. The clause provides extra information, so which is correct.

Revised example:

  • Among my new programs, I am offering a class that/which may be an excellent fit for your training needs and budget.

Does the clause (in red) introduce information that is essential to knowing which class?

Yes. The clause tells which class–a class that may be an excellent fit. Therefore, that is correct.

One way to determine  the correct word is to ask the question, “Does the clause clarify which of several possibilities is being referred to?” If the answer is yes, then the correct word to use is that. If the answer is no, the correct word to use is which.

Test yourself

  1. Craig uses the AP Stylebook, that/which newspapers and magazines follow.
  2. Michelle likes a Oaxacan restaurant that/which is on Ballard Avenue.
  3. Lynn wrote about the that/which rule, that/which confuses many people.

Answers: 1. which, 2. that, 3. which

You’ve probably noticed that “which clauses” are set off by commas–“that clauses” are not.

Sometimes that can be omitted: Michelle likes a Oaxacan restaurant on Ballard Avenue.

If you have gotten this far, which I know you have, congratulations. That is an achievement!

Related: Is There a Comma Before “Which”?

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By Lynn Gaertner-Johnston

Lynn Gaertner-Johnston has helped thousands of employees and managers improve their business writing skills and confidence through her company, Syntax Training. In her corporate training career of more than 20 years, she has worked with executives, engineers, scientists, sales staff, and many other professionals, helping them get their messages across with clarity and tact.

A gifted teacher, Lynn has led writing classes at more than 100 companies and organizations such as MasterCard, Microsoft, Boeing, Nintendo, REI, AARP, Ledcor, and Kaiser Permanente. Near her home in Seattle, Washington, she has taught managerial communications in the MBA programs of the University of Washington and UW Bothell. She has created a communications course, Business Writing That Builds Relationships, and provides the curriculum at no cost to college instructors.

A recognized expert in business writing etiquette, Lynn has been quoted in "The Wall Street Journal," "The Atlantic," "Vanity Fair," and other media.

Lynn sharpened her business writing skills at the University of Notre Dame, where she earned a master's degree in communication, and at Bradley University, with a bachelor's degree in English.

34 comments on ““That” vs “Which””

  • As a French person who wants (who tries) to write proper English, the use of ‘that’ vs ‘which’ was unclear until I saw your topic. Thanks. jym

  • I think you are wrong about “That” and “Which”. Your views follow some previous writers on the subject, but, in my opinion, you have confused the change of meaning which the commas introduce with the effect of the words themselves. I believe you are right only in part … “That’ cannot be used for a non-rstrictuve clause, but, without commas, it is perfectly legimite to use “which” to introduce a restrictive clause. there are many examples in English literature, from Dickens onwards. You are making a false rule here. The words which you are using will confuse some people !!!



  • Hi, Brian. Thank you for your opinion. Do any current reference books agree with you? All the books in my library support my explanation, so it would help me to know your sources.

    Although I appreciate his writing, I don’t count Charles Dickens as a resource for 21st-century business writers.

  • I loved everything you wrote until I got to not counting Charles Dickens as a resourse for 21st-century business writers. That was a developing trend in the 20th century, I thought we had progressed from it.
    This makes me disengage.

  • Jim, thank you for your views. You helped me realize that I had not been explicit in my previous comment. I should have written “I don’t count Charles Dickens as a GRAMMAR resource for 21st-century business writers.”

    Language and writing have evolved since the 19th century, when Dickens was writing. As a 21st-century business writer, I would not copy his punctuation or his grammar. Instead I use current business writing guides.

    Do you recommend a different approach?

  • Sir Ernest Gowers, in The Complete Plain Words: ‘That cannot be used as a commenting clause; the relative must be which. With a defining clause either which or that is permissible. When in a defining clause the relative is in the objective case, it can be left out altogether. Thus we have three variants.’

  • Mimsys, I appreciate your contributing. I am fairly certain, though, that your example does not support my view. Sir Ernest Gowers seems to state that both “that” and “which” are correct with restrictive clauses. (He calls them “defining clauses.”)

    This appears to be a UK vs. US distinction. American references do not recommend “which” for restrictive clauses.


  • I agree that the United States and the United Kingdom do not write, or speak the same English. Therefore, the UK opinions will definately differ from those of us from the good ol’ US.

  • Very amusing comment, Lyn, regarding ‘The Peasant’s’ post. The problem with avoiding the use of ‘that’ and ‘which’ in your sentences is that you risk sounding like a telegrapher!

    Janet: what you say is true, however ‘definitely’ is spelled the same in both countries. Without an ‘a’.

  • Anon,

    You’re right about the spelling; however, a conjunctive adverb connecting two independent clauses is preceded by a semi-colon and followed by a comma.

    Almost always imperfectly,


  • Miss Lynn, I see it neither as a UK v. US issue nor a battle of the centuries. It is rather more a matter of Logic versus Practice. Of course, Logic should prevail, and thus drive Practice.
    “That” is used when it would complete a sentence, were the phrase following it omitted. “Which,” on the other hand, is used when the phrase following it is descriptive.
    Would one say, “America is the country of that I speak”? I think not. Nevertheless I believe that the 21st-century business writing teachers whom you consult would have us say, “America is the country that I love and of which I speak” (assuming arguendo that they would not suggest writing “…and speak of”). And that would be totally inconsistent and illogical. “Which” is appropriate at both places in that sentence (and could even be deleted in the first instance because it precedes the nominative case, but that’s another issue).
    Furthermore, I fail to see how isolating the phrase with commas is at all relevant.
    My source: the unwashed human brain.
    Thanks for listening!

  • Hi, Todd. Thanks for weighing in. (You notice that I am comfortable ending a sentence with a preposition when it fits.) I am happy to listen.

    I do not have a copy of “The Unwashed Human Brain” on my bookshelf, so I cannot consult it.

    Only kidding.


  • Thank you so much for clarifying this!I was writing something and got stumped on this very question. Your article came up just in time.

  • Hmmm, I need to consult more sources for a definitive answer that (???!) I clearly understand.

    I think that a long list of grammer exercises invloving ‘that/which’ dilemmas would be useful. Does anybody know where I can find such a tutorial?

  • Slacker, your use of “that” in your opening sentence is correct. However, in the US many people would leave it out.

    The same is true of “that” near the beginning of your second sentence.


  • For me the Oxford Dictionary explanation at makes the most sense and is by far the easiest to understand.

    If the first part makes sense without any additional information following which or that (unrestrictive) then use “which” but NEVER “that”.

    If the first part makes little or no sense without the extra info you can use either “which” or “that”.

    The use of the comma is also clearly enunciated.

    Who could argue with this?

  • Hi, Peter. Thank you for the reference. The advice is excellent for British writers and can be useful for Americans too.

    Here’s the issue: In the US, most people avoid “which” for restrictive clauses, choosing only “that” for a sentence like this one from your “Oxford Dictionaries” page:

    –She held out the hand that was hurt.

    So although I wouldn’t argue with your prestigious reference, I did need to clarify American usage.

    Thanks for taking the time to comment.


  • Lynn,
    I was asked by a member of our firm why I had changed “that” to “which” when proofreading his letter. When I realized I could not properly explain the reason, I went online and there you were with the perfect answer. Thanks Lynn!

  • Lynn,

    I’m afraid your attempt to justify disregarding the Oxford advice is something of a fudge: if the distinction were real, you would have used it to dismiss Dickens, instead of pointing to an unsubstantiated change in English. Oxford routinely provides different advice for American and British writers when it applies. You asked for an authority. The linguists at the Language Log have pounded away against your position, terming the distinction the “totally fake which-that rule.” ( Pullum goes on to provide a more nuanced basis for distinguishing the two, a position which [note the usage] I develop, modify, and elaborate in “The Subtle Distinction between ‘that’ and ‘which.'” (

  • Hi, Stephen. The “Oxford Dictionaries” page itself gives reason for Americans to qualify its advice. The top of the page reads, “In many cases, in British English, both words are equally correct.” It does not address American English.

    My many years of experience as a business writer in the United States, my education in the English language, and a review of respected style guides have led me to offer the explanations I have given above. I don’t have anything else to say on the topic or its nuances.

    Best regards,


  • The “which”-follows-comma rule is, I think, a good one. Otherwise remove “that”/”which” from your sentance. If it makes sense, go with “that”; if not, “which” is your correct word. I wish I could remember where I read this.

  • As for us Canadians, caught between our English (sometimes) heritage and Commonwealth connections, and our close ties, family, business and geographic, to the U.S., we’re always flipping between one set of rules and spellings (neighbor, neighbour) and the other. The Guardian newspaper stylebook says:

    that or which?
    This is quite easy, really: “that” defines, “which” gives extra information (often in a clause enclosed by commas):

    This is the house that Jack built; but this house, which John built, is falling down.
    The Guardian, which I read every day, is the paper that I admire above all others.
    I am very proud of the sunflowers that I grew from seed (some of the sunflowers);
    I am very proud of the sunflowers, which I grew from seed (all the sunflowers).

    Note that in such examples the sentence remains grammatical without “that” (the house Jack built, the paper I admire, the sunflowers I grew), but not without “which”

  • Thanks for the help here, I just think it’s funny that you have written “a Oaxacan restaurant” instead of “an Oaxacan restaurant”. Ha ha!

  • Hi, Lesley. The article before “Oaxacan” is “a” because “Oaxacan” begins with a “w” sound. Compare these:

    a Oaxacan restaurant
    a white envelope
    a wicked sense of humor


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