Whom should be used to refer to the object of a verb or preposition. When in doubt, try this simple trick: If you can replace the word with “he”’ or “’she,” use who. If you can replace it with “him” or “her,” use whom.

Who should be used to refer to the subject of a sentence.

should be used to refer to the subject of a sentence. Whom should be used to refer to the object of a verb or preposition.

Who or whom? If you’re like most English speakers, you know that there’s a difference between these pronouns, but you aren’t sure what that difference is. After reading this article, you might conclude that knowing when to use who or whom is not as difficult as you think.

Here’s a tip: Want to make sure your writing always looks great? Grammarly can save you from misspellings, grammatical and punctuation mistakes, and other writing issues on all your favorite websites.

Confused about who and whom? Let Grammarly help you choose the right word. Get Grammarly

When to Use Who

In a sentence, who is used as a subject. Let’s look at a couple of examples:

Who would like to go on vacation?

Who made these awesome quesadillas?

When to Use Whom

Whom is used as the object of a verb or preposition. Consider these examples:

To whom was the letter addressed?

Whom do you believe?

I do not know with whom I will go to the prom.

The Difference Between Who and Whom

How can you tell when your pronoun is the object of a verb or preposition? Try substituting “he” or “she” and “him” or “her.” If “he” or “she” fits, you should use who. If “him” or “her” fits, you should use whom. Keep in mind that you may have to temporarily rearrange the sentence a bit while you test it.

Who/whom ate my sandwich?

Try substituting “she” and “her”: She ate my sandwich. Her ate my sandwich. “She” works and “her” doesn’t. That means the word you want is who.

Whom ate my sandwich?

Who ate my sandwich?

Let’s look at another:

Who/whom should I talk to about labeling food in the refrigerator?

Try substituting “he” and “him”: I should talk to he. I should talk to him. “Him” works, so the word you need is whom.

Whom should I talk to about labeling food in the refrigerator?

You can also use questions to determine when to use who and when to use whom. Are you talking about someone who is doing something?

Gina drives her mother’s car to school.

Yes, you are talking about someone doing something, so use who in your question.

Who drives her mother’s car to school?

Now look at this sentence:

The car is driven to school by Gina.

No, the subject of the sentence (car) is not performing the action. Use whom in your question.

The car is driven to school by whom?

By whom is the car driven to school?

If you think the whom examples sound awkward or prissy, you are not alone. Many people don’t use whom in casual speech or writing. Others use it only in well-established phrases such as “to whom it may concern.” Some people never use it. It’s not unusual at all to hear sentences like these:

Who do you believe?

Who should I talk to about labeling food in the refrigerator?

Who vs. Whom Quiz