Whose vs. Who's: What's the Difference?

Knowing the difference between "whose" and "who's" is child's play once you know some easy rules. Alias Ching/Shutterstock

Whose and who's. The two words sound alike, don't they?

One of these words is the possessive form and means "belonging to a person," while the other word is a contraction of "who is." Right now, it may seem easy to tell "whose" from "who's," but when it comes to putting these words into play, things often get murky.

While "whose" and "who's" may sound the same, they are markedly different when it comes to spelling, meaning and usage. If you've had trouble deciding which word to use, whose vs. who's, read on. We have some helpful tips that will have you choosing the correct word in no time.

Different Words, One Origin

Despite their differences in spelling, meaning and usage, the words "who's" and "whose" have the same origins: the word "who."

"Who" is a pronoun. A pronoun is a word that can be substituted for another noun when a reader or listener already knows which noun you're referring to. For example, while "who" is a pronoun, so are these common words: I, she, he, you, it, we or they.

"Who" is known as a subject pronoun, which means it is used to refer to animate objects like people. For example, it could be used in the statement, "She is someone who likes carrots."

It is also a relative pronoun. Relative pronouns introduce relative clauses, which are a type of dependent clause. Relative clauses modify a word, phrase or idea in the main clause. An example of this is a sentence such as:

The man, who lives in a house, is my friend.

When you use the word "who," you are using the pronoun to mean "what or which person or people."

Whose vs. the Contraction Who's

The word "who's" is simply a shortened form, or contraction, of the two words "who is" or "who has." For example, instead of asking "Who is coming to dinner tonight?" the contraction could be used to ask, "Who's coming to dinner tonight?"

The apostrophe in "who's" stands in for the missing letter "i" in "who is" or the missing letters "ha" in "has."

The proper usage of the word "whose," on the other hand, is entirely different. "Whose" is used to mean "belonging to whom." It is a possessive form of the pronoun that signals "of or relating to whom or which."

A possessive pronoun like "whose" is often used to show ownership. Take the following sentence examples:

• "Whose shoes are these?" This means, who do these shoes belong to?

• "I wonder whose book was left on the sofa." This means, I wonder who owns the book on the sofa?

In addition, the correct way of using the possessive pronoun "whose" can extend beyond ownership. "Whose," in some other examples, can refer to being on the receiving end of an action, or it can be used to express an association with something.

• This is a country whose economy is booming.

• She has a son whose ambition is to be a novelist.

A Trick to Help You Tell the Difference

Knowing when to use "whose" and when to deploy "who's" may seem daunting at first. However, there is one handy test you can use to know whether you're using "whose" or "who's" properly — and it all has to do with a simple apostrophe. For example, consider the following sentence:

• I found a wallet, but I don't know who's/whose it is.

If you're unsure whether to use "who's" or "whose" in a sentence like the one above, then try removing the apostrophe in "who's" and saying "who is" as a test. The apostrophe stands for the "i" in the contraction. Does it make sense in that context?

If, for example, you say "I found a wallet, but I don't know who is it is," you'll immediately know it doesn't sound right. Therefore, "who's" is not the right word to use; instead, "whose" is the correct choice.