That vs. Which: When to Use Which vs. That (with Useful Examples)

Last Updated on December 18, 2023

If there’s one pair of words in the English language that causes even the most experienced writers to stop for a second and think about which is the correct word to use, then it’s that vs. which. Both these words can be used in many different contexts in a sentence but when one of the two is needed as a relative pronoun, a real nightmare can start. However, don’t start panicking: with that vs. which, there’s a perfectly logical explanation that will help you always use only the correct word.

That vs. Which: What is the Difference? 

When it comes to using which or that as relative pronouns, you should be very careful about which choice you make. While both of them can be used when you’re talking about an inanimate object or an animal that doesn’t have a name, only “that” can be used when you’re talking about a human being.

But how to choose the correct word? Well, according to the American English rules, THAT should be used when you have a restrictive, or an essential clause, while WHICH should be used when the clause is nonrestrictive, or nonessential.

That vs. WhichPin

Key Takeaways

“That” is used to introduce essential clauses, also known as restrictive clauses, which provide information that is crucial to the meaning of the sentence. These clauses are not set off by commas.

“Which” introduces non-essential clauses, or non-restrictive clauses, which add extra information that could be left out without changing the overall meaning of the sentence. These clauses are typically set off by commas.

Remember to use “that” without commas to indicate a specific item or items being referred to, and “which” with commas for adding non-essential details.

Fundamentals of That and Which

That is commonly used in restrictive clauses—parts of a sentence that are essential to its meaning. Without these clauses, the sentence’s core message would change. Restrictive clauses do not have commas around them. Consider the sentence: “The books that are on the shelf are overdue.” Here, “that are on the shelf” tells us exactly which books we’re talking about—it restricts the subject to only those books.

Which, on the other hand, is used in nonrestrictive clauses. These clauses provide additional, but not essential, information—it can be removed without altering the meaning of a sentence. Nonrestrictive clauses are usually set off with commas. For example: “The books, which have red covers, are overdue.” In this case, “which have red covers” offers extra info and could be omitted: “The books are overdue.”

When to Use That and Which 

When to Use That

A restrictive clause is the one that you can’t just get rid of because it’s necessary to understand the meaning of the sentence. It makes the meaning more specific by narrowing a big category to a smaller one. For instance, in the sentence “All visitors that are underaged must be accompanied by their parents”, you can’t cross out the clause. If you do that, the sentence will read, “All visitors must be accompanied by their parents” and this simply wouldn’t make a lot of sense. So, because the clause is essential, you need to use that.

When to Use Which

In contrast, a nonrestrictive clause isn’t necessary. Sure, it gives some additional information but if you don’t use one, your readers will still be able to understand the sentence. For example, you can say, “My house, which is located in Texas, was built fifty years ago”. Even if you don’t specify that your house is in Texas, the meaning of the sentence stays the same. Therefore, the pronoun that you should use is which.

Useful Tips for Using 

Note that a restrictive clause doesn’t need commas, while a nonrestrictive clause does. This is one more clue that will help you pick the correct word. These commas are very important because, depending on whether you have them or not, you can change the meaning of the sentence completely. For example, look at these two sentences:

  1. The long letter that I received yesterday came from New Zealand.
  2. The long letter, which I received yesterday, came from New Zealand.

When the reader sees the first sentence, he will assume that you have many long letters, so you need to specify that you received the one you’re talking about yesterday. It’s possible that a dozen other long letters found you the day before yesterday, last week or last month. This is why you can’t cross out the clause here.

In the second sentence, however, the fact that you received the letter yesterday doesn’t add any essential information. The reader understands that you have only one long letter, and the fact that you received it yesterday doesn’t change anything. If you cross out everything that is in between the commas, the sentence will still make sense.

As the Chicago Manual of Style teaches us, if you have a preposition and need a relative pronoun, you can only use which. For instance, if one of your friends graduated from a very well-known university, the correct way of telling everyone about it would be, “The university from WHICH he graduated is very well-known”.

If you still aren’t a 100% sure about the distinction between that vs. which, there’s no reason to worry because, in fact, these details are only really observed in American English. You’ll often see British writers using either which or that not depending on whether the clause is essential or nonessential but simply because they feel like it.

Still, if you want to follow all the rules, remember that you can throw all the “whiches” out without losing any of the meaning, while all the “thats” should stay in place. If you remember this, you’ll have no problem figuring out when to use each pronoun.

That vs. Which Examples

Examples of “That” in Sentences

  • The book that I borrowed from you is excellent.
  • She is looking for the dress that she wore last weekend.
  • The test that we took yesterday was very difficult.
  • He wants to buy the car that has the best fuel efficiency.
  • The cake that she baked for the party was delicious.

Examples of “Which” in Sentences

  • The car, which is parked outside, is mine.
  • She showed me her new dress, which is blue and white.
  • The book, which I read last night, was very interesting.
  • He explained the problem, which seemed quite complicated at first.
  • The movie, which won several awards, is showing at the local theater.

Examples of Sentences that Use Both “That” and “Which”:

  • That is the hotel which we stayed at during our vacation.
  • She couldn’t remember the name of the person that called, which was important.
  • The painting that hangs in the hall, which is a family heirloom, is over a hundred years old.
  • I need to find the report that I was working on, which has to be submitted by tomorrow.
  • The team that wins the match, which is the final game of the season, will take home the trophy.

Quiz: Test Your Knowledge

Question 1: Choose the correct word.
The book __ (that/which) is on the table is mine.

Question 2: Fill in the blank.
The car, __ (that/which) I bought last year, is already having issues.

Question 3: True or False.
A restrictive clause limits the meaning of the noun it refers to.

Question 4: Select the right option.
I have a friend __ (that/which) can speak six languages.

Question 5: Identify whether the clause is restrictive or nonrestrictive.
The park, by our house, has a lake. (Restrictive/Nonrestrictive)

Here are hints to guide us:

  • If the sentence wouldn’t make sense without the clause, use “that.”
  • Commas often accompany “which” since the information is supplementary.
No. Your Answer Correct Answer
1.   that
2.   which
3.   True
4.   that
5.   Nonrestrictive

FAQs About That vs. Which

When do we use “that”?
We use “that” in restrictive clauses, which are essential to the noun they’re referring to. It’s like giving crucial information without which the sentence wouldn’t make much sense.

  • Example: The book that she read was engaging.

When do we use “which”?
We turn to “which” for nonrestrictive clauses, providing extra information that could be left out without changing the fundamental meaning of the sentence. These clauses are usually set apart by commas.

  • Example: The book, which she read last weekend, was engaging.

Is it okay to use “which” in restrictive clauses?
Typically, in American English, we reserve “which” for nonrestrictive clauses. However, “which” might be seen in restrictive clauses in British English or in cases where it sounds more natural.

Can “that” and “which” be used interchangeably?
No, they usually shouldn’t be swapped because they serve different functions in a sentence. Using them incorrectly could lead to ambiguity or a change in meaning.

4 thoughts on “That vs. Which: When to Use Which vs. That (with Useful Examples)”

    • I had this same thought and was wishing to have someone to verify this with me.
      Im a beginner with these very technical grammar rules but I believe I’ve found another questionable grammar error, which is seen near the end of the article.
      *Question 3: True or False.
      “A restrictive clause limits the meaning of the noun it refers to.”
      Have you heard the phrase: we should never end a sentence with a preposition?
      Because the word *to* is a preposition, I would feel more comfortable with their sentence rearranged like the following sentence.
      “A restrictive clause limits the meaning of the noun to which it refers.”
      What do you think?


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