What Does "Who's" Mean?
Who's is a contraction. The apostrophe marks a missing letter:
- Who's = who is: Who's going to lead the project? (Who is going to lead the project?)
- Who's = who has: Who's already submitted their report? (Who has already submitted their report?)
More examples of who's:
- Do you know who's responsible for this? (who is)
- She's the one who's been managing the account. (who has)
- Who's coming to the meeting tomorrow? (who is)
- That's the candidate who's received the most votes so far. (who has)
The expansion test: if you can replace who's with who is or who has and the sentence still makes sense, the contraction is correct.
What Does "Whose" Mean?
Whose is the possessive form of who (and also of which, for objects). It modifies a noun by showing that the noun belongs to or is associated with someone.
- Whose report is this? (to whom does this report belong?)
- The employee whose proposal was selected will present next week.
- I don't know whose idea it was.
- She's the author whose work I admire most.
- That's the building whose renovation was completed last year. (whose used for an object)
Whose is never expandable into two words. It is a standalone possessive pronoun/determiner.
The Expansion Test
Before writing either word, substitute who is or who has into the sentence:
- "[Who is] responsible?" → makes sense → who's responsible.
- "[Who is] jacket is this?" → does not make sense → whose jacket is this.
- "[Who has] been in charge?" → makes sense → who's been in charge.
- "[Who is] recommendation was strongest?" → does not make sense → whose recommendation was strongest.
"Whose" for Objects and Things
A common misconception is that whose can only refer to people. In standard English, whose is also used for objects, animals, and abstractions when you need to indicate possession but of which would be awkward.
- The committee, whose report was released on Friday, met three times this week.
- This is a policy whose effects are still being studied.
- The old building, whose walls were three feet thick, survived the earthquake.
The alternative — the building the walls of which were three feet thick — is grammatically correct but awkward. Most style guides accept whose for non-human nouns.
Common Errors
| Incorrect | Correct | Why |
|---|---|---|
| Who's car is parked outside? | Whose car is parked outside? | The car belongs to someone — possessive is needed. "Who is car" makes no sense. |
| That's the manager whose coming next. | That's the manager who's coming next. | "Who is coming" — a contraction is needed, not a possessive. |
| Do you know who's idea this was? | Do you know whose idea this was? | "Who is idea" makes no sense — possession requires whose. |
| Whose going to handle the revisions? | Who's going to handle the revisions? | "Who is going" — a contraction is needed. |
The Broader Pattern: Possessives Never Take Apostrophes
The who's / whose confusion follows the same pattern as its / it's, your / you're, and their / they're. In all cases, the possessive pronoun has no apostrophe, and the contraction does. This is a reliable rule across the entire system:
| Possessive (no apostrophe) | Contraction (apostrophe) |
|---|---|
| whose (belonging to who) | who's (who is / who has) |
| its (belonging to it) | it's (it is / it has) |
| your (belonging to you) | you're (you are) |
| their (belonging to them) | they're (they are) |
Frequently Asked Questions
Can "whose" refer to a company or organization?
Yes. Whose applies to any entity, not only individual people: The company whose products were recalled has issued a statement. The organization whose funding was cut responded with a formal complaint.
Is "who's" ever possessive?
No. Who's is only ever a contraction of who is or who has. Possession always requires whose. This is a hard rule with no exceptions.
What is the difference between "whose" and "of whom"?
Both express possession, but whose is more natural in most contexts. The author whose book I enjoyed and the author of whose book I was fond are equivalent, but the latter is stilted. Of whom is more common when the possessive follows a preposition or when the phrasing calls for it: the colleague of whom I spoke earlier. In most sentences, whose is the cleaner choice.