Choosing between to who or to whom can be confusing, but the correct choice is usually to whom because the word follows the preposition to. In English grammar, whom is an object pronoun, while who is a subject pronoun.
However, in everyday spoken English, many people use who instead of whom, especially in informal conversations.
This guide explains the grammar rule in simple words. You’ll learn the difference between who and whom, where each belongs in a sentence, how formal English differs from informal English, and how to avoid common grammar mistakes.
Whether you’re writing emails, academic papers, business communication, or social media posts, you’ll know which form to use with confidence.
Quick Answer
The correct phrase is to whom whenever the pronoun is the object of a preposition.
Correct examples
- To whom should I address the letter? ✅
- To whom does this package belong? ✅
- To whom were you speaking? ✅
Informal examples
- Who should I send this to? ✅ (Natural in everyday conversation)
- Who were you talking to? ✅ (Common in spoken English)
Incorrect examples
- To who should I address the letter? ❌
- To who does this package belong? ❌
Why?
In Standard English, the preposition to requires an object pronoun. Since whom is the object form of who, to whom is grammatically correct.
Think of it this way:
- Who = Subject Pronoun
- Whom = Object Pronoun
Examples:
- Who called you? (Who is the subject.)
- Whom did you call? (Whom is the direct object.)
- To whom did you send the email? (Whom is the object of the preposition “to.”)
If you’re writing academic writing, professional emails, business writing, formal letters, or research papers, use to whom. In casual conversation, many native speakers choose who, but formal grammar still prefers whom after a preposition.
The Origin of To Who or To Whom
The difference between who and whom comes from the history of the English language.
Both words developed from Old English, where pronouns changed form depending on their role in a sentence. Just as he becomes him and they becomes them, who changes to whom when it functions as an object.
Over time, everyday speech became simpler. Native speakers gradually stopped using whom in many informal situations. Today, who is common in conversations and on social media, while whom remains important in formal English, professional writing, legal documents, academic writing, and other situations where correct grammar matters.
The phrase to whom has stayed almost unchanged because grammar rules require an object pronoun after a preposition. That is why expressions like “To whom it may concern” continue to appear in cover letters, formal letters, official notices, and business communication.
Understanding this history makes it easier to remember why to whom is still the preferred choice in formal writing, even though to who is often heard in everyday conversation.
British English vs American English Spelling
Many learners wonder whether British English and American English treat to who and to whom differently. The answer is simple: they do not.
Unlike spelling pairs such as colour/color or traveller/traveler, who and whom have the same spelling in both varieties of English. The difference is purely a matter of grammar, not spelling.
The main difference is how often whom is used.
- British English keeps whom more often in formal writing and official communication.
- American English also uses whom in formal contexts, but many writers and speakers prefer who in everyday language.
- In Standard English, both countries still recommend to whom after the preposition to.
Comparison Table
| Feature | British English | American English |
| Spelling of who | Who | Who |
| Spelling of whom | Whom | Whom |
| Formal writing | Frequently uses whom | Uses whom when grammar requires it |
| Everyday conversation | Often replaces whom with who | Very commonly replaces whom with who |
| Academic writing | To whom is preferred | To whom is preferred |
| Business writing | To whom is recommended | To whom is recommended |
Examples
| Formal Sentence | Informal Alternative |
| To whom should I send the report? | Who should I send the report to? |
| To whom was the award presented? | Who was the award presented to? |
| To whom does this account belong? | Who does this account belong to? |
No matter whether you write for a UK, US, Canadian, Australian, or global audience, to whom remains the grammatically correct choice when the pronoun is the object of a preposition.
Pronunciation of To Who or To Whom
One reason people confuse to who or to whom is that the two phrases sound very similar in spoken English.
Pronunciation
- To who → /tə huː/
- To whom → /tə huːm/
The only noticeable difference is the “m” sound at the end of whom.
Because many native speakers speak quickly, that final sound may be very soft or almost disappear. As a result, listeners often hear who even when the speaker actually says whom.
Does pronunciation change the grammar?
No.
The pronunciation does not affect the grammar rule.
For example:
- To whom did you speak yesterday? ✅
- To whom should I send the invitation? ✅
- Who should I send this invitation to? ✅ (Natural and informal)
Whether you’re speaking or writing, remember this simple rule:
- Who acts as the subject of a verb.
- Whom acts as a direct object, indirect object, or the object of a preposition.
Quick Test
Replace the word with he/him.
- If him sounds correct, use whom.
- If he sounds correct, use who.
Example:
To whom did you send the email?
Try replacing it:
- I sent it to him. ✅
- I sent it to he. ❌
Since him is correct, whom is the right choice.
Why People Confuse To Who or To Whom
The confusion between to who and to whom has become more common because modern English has changed over time.
Here are the biggest reasons people mix them up.
1. Everyday Speech Uses “Who”
In casual conversation, many native speakers rarely say whom.
Instead of saying:
- To whom were you talking?
they naturally say:
- Who were you talking to?
This makes learners believe to who is also correct, even though it isn’t in formal English.
2. The Grammar Rule Is Often Forgotten
Many people no longer remember the difference between a subject pronoun and an object pronoun.
Remember:
- Who = Subject
- Whom = Object
Understanding sentence structure, verbs, and prepositional phrases makes this rule much easier.
3. Schools Focus Less on “Whom”
Many modern writing guides accept who in informal writing because it sounds more natural.
However, teachers, editors, proofreaders, and professional writers still expect whom in formal letters, reports, research papers, technical writing, and other forms of academic writing.
4. Social Media Encourages Informal Grammar
Platforms like social media, text messages, and online chats prioritize speed over perfect grammar.
As a result, phrases such as “Who should I send it to?” appear much more often than “To whom should I send it?”
Both are understood, but only one follows traditional English grammar.
5. Formal and Informal English Have Different Expectations
The choice often depends on your audience.
- Writing a university essay? Use to whom.
- Sending a business email? Use to whom where appropriate.
- Chatting with friends? Who sounds more natural and is widely accepted.
Knowing the difference helps improve your writing skills, communication skills, and overall confidence in correct English usage.
Which Spelling Should You Use?
The choice between to who and to whom is not about spelling. It is about using the correct English grammar. Both British English and American English spell these words the same way. The difference depends on whether the pronoun is the subject or the object in the sentence.
Use to whom when the pronoun is the object of a preposition. Use who when it is the subject of a verb.
For Academic Writing
If you are writing an essay, research paper, assignment, or university report, follow Standard English.
Examples
- To whom should the research findings be submitted? ✅
- To whom does this reference belong? ✅
For Business Writing
In professional emails, business communication, formal letters, and cover letters, to whom is the safest and most professional choice.
Examples
- To whom it may concern ✅
- To whom should I send my application? ✅
Using whom in formal documents shows strong writing skills and careful attention to grammar.
For Everyday Conversation
In everyday speech, native speakers often prefer who because it sounds more natural.
Examples
- Who should I send this to? ✅
- Who were you talking to? ✅
These sentences are common in informal English, even though formal grammar prefers to whom.
For a Global Audience
| Situation | Best Choice |
| Academic writing | To whom |
| Business writing | To whom |
| Formal email | To whom |
| Resume or cover letter | To whom |
| News article | Usually to whom |
| Social media | Usually who |
| Casual conversation | Usually who |
Quick Rule
Ask yourself one question:
Can I replace the word with “him” or “them”?
If the answer is yes, choose whom.
Examples
- I sent the message to him. → To whom did you send the message? ✅
- He sent the message. → Who sent the message? ✅
The he/him test is one of the easiest ways to choose the correct pronoun.
Common Mistakes with To Who or To Whom
Many English language learners, writers, and even native speakers make these common grammar mistakes. Learning them will improve your English usage, writing skills, and communication skills.
| Incorrect | Correct | Reason |
| To who should I write? | To whom should I write? | Whom is the object of the preposition to. |
| To who did you give the keys? | To whom did you give the keys? | The pronoun receives the action. |
| Who did you send the package to? | Correct in informal English | Common in everyday conversation. |
| To whom did you send the package? | Correct in formal English | Preferred in academic and professional writing. |
| Who called you? | Correct | Who is the subject. |
| Whom called you? | Incorrect | Whom cannot be the subject of a sentence. |
Mistake 1: Using “Who” After a Preposition
❌ To who should I send this report?
✅ To whom should I send this report?
Because to is a preposition, it requires the object pronoun whom.
Mistake 2: Using “Whom” as the Subject
❌ Whom wants to join the meeting?
✅ Who wants to join the meeting?
The person performing the action is the subject, so who is correct.
Mistake 3: Never Using “Whom”
Many people avoid whom because it sounds formal.
However, whom is still recommended in:
- Academic writing
- Business writing
- Professional emails
- Technical writing
- Legal documents
- Formal reports
Using whom correctly makes your writing sound more polished and professional.
To Who or To Whom in Everyday Examples
Here are some real-life examples that show how these pronouns are used in different situations.
Professional Email
- To whom should I address this email? ✅
- To whom may I send the signed contract? ✅
Business Communication
- To whom should customer complaints be directed? ✅
- To whom does this invoice belong? ✅
Academic Writing
- To whom should students submit their assignments? ✅
- To whom should the research proposal be sent? ✅
Formal Letter
- To whom it may concern
This remains one of the most common greetings in formal English.
News Writing
- Police have not confirmed to whom the money belonged.
Social Media
People commonly write:
- Who should I send this to?
- Who was this message meant for?
These are acceptable in informal English, although to whom is still preferred in formal writing.
Everyday Conversation
Friend:
Who were you talking to?
Teacher:
To whom were you speaking?
Both sentences are understandable, but the second follows traditional English grammar.
Easy Trick to Remember To Who or To Whom
You don’t need to memorize difficult grammar rules. Use this simple trick whenever you’re unsure.
The He/Him Test
Replace the word with he or him.
- If he sounds correct, use who.
- If him sounds correct, use whom.
Example 1
Who called you?
→ He called you.
✅ Use who.
Example 2
To whom should I send the invitation?
→ I should send it to him.
✅ Use whom.
One More Easy Rule
After these common prepositions, whom is usually correct in formal English:
- To whom
- For whom
- With whom
- From whom
Remember this simple pattern, and you’ll avoid most grammar mistakes in formal writing, proofreading, and professional communication.
To Who or To Whom – Google Trends & Usage Data
The phrase to whom continues to be the preferred choice in formal English, while who appears much more often in spoken English and informal writing.
Search interest shows that many English language learners, students, writers, and professionals look for “to who or to whom” because they are unsure which pronoun is grammatically correct. This topic is especially popular among people improving their writing skills, academic writing, and business communication.
Where Is “To Whom” Used Most?
| Audience | Preferred Usage |
| Academic writing | To whom |
| Business writing | To whom |
| Professional emails | To whom |
| Legal documents | To whom |
| Formal letters | To whom |
| Everyday conversation | Usually who |
| Social media | Usually who |
Popularity by English-Speaking Region
| Country/Region | Common Preference |
| United States | Who in conversation, to whom in formal writing |
| United Kingdom | To whom is more common in formal writing |
| Canada | Similar to UK and US |
| Australia | To whom for formal communication |
| New Zealand | To whom in professional writing |
| International English learners | Often search for the grammar rule before writing |
Although who is becoming more common in everyday speech, to whom remains the recommended choice in Standard English whenever the pronoun is the object of a preposition.
To Who or To Whom Comparison Table
| Feature | To Who | To Whom |
| Grammatically correct after to | ❌ No | ✅ Yes |
| Uses a subject pronoun | ✅ Yes | ❌ No |
| Uses an object pronoun | ❌ No | ✅ Yes |
| Suitable for academic writing | ❌ Rarely | ✅ Yes |
| Suitable for business writing | ❌ No | ✅ Yes |
| Common in spoken English | ✅ Very common | ✅ Sometimes |
| Formal English | ❌ Usually avoided | ✅ Recommended |
| Example | To who should I write? ❌ | To whom should I write? ✅ |
FAQs
Is “to who” ever correct?
In formal English, to who is considered incorrect because the preposition to requires the object pronoun whom. However, many native speakers say who in casual conversation.
Why is “to whom” grammatically correct?
Whom is the object pronoun. Since to is a preposition, it must be followed by an object, making to whom the correct choice.
Is “who” replacing “whom” in modern English?
Yes. In everyday speech and social media, who is much more common. Even so, whom is still expected in formal writing, academic writing, and business communication.
Should I use “to whom” in professional emails?
Yes. If you are writing a professional email, cover letter, or other formal document, to whom is the better choice.
Is “To Whom It May Concern” still correct?
Yes. To Whom It May Concern is still a correct and widely accepted greeting when you do not know the recipient’s name.
How can I quickly tell whether to use who or whom?
Use the he/him test.
- If he fits, use who.
- If him fits, use whom.
This simple rule works in most sentences.
Is “whom” old-fashioned?
Not exactly. While whom is less common in conversation, it remains an important part of Standard English and is widely used in formal documents and professional communication.
Conclusion
Choosing between to who or to whom becomes easy once you understand the grammar rule. Who is a subject pronoun, while whom is an object pronoun. Because to is a preposition, the correct formal expression is to whom.
Although many native speakers use who in everyday conversation, to whom is still the preferred choice in academic writing, business writing, professional emails, and other forms of formal English. When you’re unsure, use the simple he/him test. It helps you choose the correct pronoun quickly and write with confidence.
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Hi, I am Roy Peter Clark, and I write clear and practical grammar and writing blogs.
On Syntaxiffy.com, I focus on English grammar, style, and writing techniques to help readers improve clarity and communication.
