If you’ve ever paused mid-sentence wondering when to use whom or who, you’re not alone. Even confident writers hesitate here. The good news? The rule is simpler than most people think. Once you understand how each word functions in a sentence, you’ll know exactly when to use whom or who in a sentence—and you won’t second-guess yourself again.
This guide breaks it down in plain language, with real examples, quick tests, and practical tips you can use immediately.
The Basic Rule for Who vs. Whom
Here’s the core difference:
-
Who = subject (the person doing the action)
-
Whom = object (the person receiving the action)
Think of it this way:
-
If the person acts, use who.
-
If the person is acted upon, use whom.
Examples:
-
Who called you? (Who = subject, doing the calling)
-
Whom did you call? (Whom = object, receiving the call)
This simple subject–object rule is the foundation for knowing when to use whom or who.
The Easy He/Him Test (Your Best Shortcut)
If grammar terms feel abstract, use this quick trick:
Replace the word with he or him.
-
If he fits → use who
-
If him fits → use whom
Examples:
-
(Who/Whom) is coming to dinner?
He is coming.
Who is coming to dinner? -
To (who/whom) should I address the letter?
I should address it to him.
To whom should I address the letter?
This is the fastest way to decide when to use whom or who in a sentence.
When to Use “Who” (Subject Examples)
Use who when the person is the subject of the sentence or clause.
Common situations:
-
Asking a question
-
Introducing a relative clause
-
Identifying someone who performs an action
Examples:
-
Who wrote this report?
-
She is the manager who approved the budget.
-
Do you know who won the award?
Tip: If the verb comes right after the word, it’s usually who.
When to Use “Whom” (Object Examples)
Use whom when the person is the object of a verb or preposition.
Look for these clues:
-
Words like to, for, with, by, about
-
The person receives the action
Examples:
-
Whom did you invite?
-
The client whom we met yesterday signed the contract.
-
With whom are you traveling?
Quick check: If you can answer with him/her/them, “whom” is correct.
Formal vs. Modern Usage
In everyday conversation, many people use who instead of whom, and it’s widely accepted in informal contexts.
Formal writing (recommended):
-
To whom it may concern
-
The candidate whom we selected
Casual speech (common):
-
Who did you send the email to?
If you’re writing professionally, academically, or for SEO content, it’s best to use whom correctly where required.
Common Mistakes (and How to Fix Them)
Mistake 1: Using “whom” just to sound formal
Wrong: Whom is coming to the meeting?
Correct: Who is coming to the meeting?
Mistake 2: Ignoring the preposition
Wrong: Who are you speaking to? (formal writing)
Correct: To whom are you speaking?
Mistake 3: Getting confused in complex sentences
Example:
-
She didn’t know who would respond.
(“Who” is the subject of would respond, so it’s correct.)
When in doubt, isolate the clause and apply the he/him test.
Quick Reference Cheat Sheet
Use WHO when:
-
The person does the action
-
You can replace it with he/she/they
Use WHOM when:
-
The person receives the action
-
It follows a preposition
-
You can replace it with him/her/them
FAQs About Who vs. Whom
1. Is “whom” still necessary?
Yes, especially in formal writing, business communication, academic work, and professional content.
2. Can I always use “who” instead?
In casual conversation, usually yes. In formal contexts, incorrect usage can look unprofessional.
3. What about “Who did you give it to?”
Informally acceptable. Formally: To whom did you give it?
4. Is “To whom it may concern” still correct?
Yes. It’s a standard formal phrase and a classic example of proper “whom” usage.
5. Why is this rule confusing?
Because spoken English has gradually reduced the use of “whom,” but formal grammar standards still recognize it.
Conclusion
Mastering when to use whom or who comes down to one simple idea: subject vs. object. If the person performs the action, use who. If the action is done to them, use whom. When you’re unsure, the he/him test will give you the answer in seconds.
Getting this right sharpens your writing and boosts your credibility—especially in professional or academic settings. If you want to improve further, practice by reviewing your emails, articles, or social posts and checking when to use whom or who in a sentence.
