If you’ve ever paused while writing a sentence such as “I interviewed ten applicants, some of who had years of experience,” you’re not alone. Some of whom and some of who look almost identical, yet standard English treats them differently. The confusion usually comes from the fact that who and whom both refer to people. The real difference comes from their grammatical roles within a sentence.
In most formal and standard English writing, “some of whom” is the correct expression. The word whom works as the object of the preposition of, while who generally works as a subject. Once you understand this small distinction, the choice becomes much easier. This guide explains some of whom vs. some of who, shows exactly why one form works, compares related constructions, and provides plenty of examples you can use in everyday, academic, and professional writing.
Quick Answer
“Some of whom” is the standard and grammatically correct expression when referring to part of a group of people.
For example:
I invited twelve guests, some of whom arrived early.
Here, whom follows the preposition of, so it takes the object form.
By contrast:
I invited twelve guests, some of who arrived early.
In standard English, some of who is generally considered incorrect in this construction.
A simple way to remember the rule is:
- Who → usually acts as the subject.
- Whom → usually acts as the object.
- Of → requires an object in this construction.
- Therefore, some of whom is the standard form.
You can also rewrite the sentence using some of them:
I invited twelve guests. Some of them arrived early.
Both sentences communicate essentially the same idea. The difference is grammatical structure and style.
Comparison Overview
| Expression | Standard English | Function | Example |
| Some of whom | Correct | Refers to part of a group of people | She knows several doctors, some of whom specialize in surgery. |
| Some of who | Generally incorrect | Doesn’t fit the standard object construction | She knows several doctors, some of who specialize in surgery. |
| Some of them | Correct | Independent pronoun phrase | She knows several doctors. Some of them specialize in surgery. |
| Some who | Correct in certain structures | Refers to people who perform an action | Some who attended the meeting stayed afterward. |
| Some of which | Correct for things | Refers to part of a group of things | She reviewed ten reports, some of which contained errors. |
| Some of whose | Correct for possession | Shows ownership or association | She interviewed several writers, some of whose books became bestsellers. |
The important point is that some of whom and some of who aren’t simply interchangeable spelling choices. The words who and whom perform different grammatical jobs.
Main Differences Between Some of Whom vs. Some of Who
The biggest difference between some of whom and some of who comes down to grammatical case.
Who is traditionally called the subjective form, while whom is the objective form. English speakers use who when the person performs an action and whom when the person receives an action or follows a preposition.
Consider these examples:
The students who studied passed the exam.
The students perform the action of studying, so who acts as the subject.
Now compare:
The students, some of whom studied all night, passed the exam.
The phrase some of whom contains the preposition of. The pronoun functions as the object of that preposition. Therefore, whom fits the standard grammatical pattern.
The Basic Grammatical Difference
| Word | Traditional role | Example |
| Who | Subject | Who called you? |
| Whom | Object | Whom did you call? |
| Whom | Object after a preposition | Of whom are you speaking? |
The distinction may seem formal because many people rarely use whom in casual conversation. However, the construction some of whom remains common and useful in polished writing.
Why “Some of Whom” Is Correct
To understand some of whom, it helps to break the phrase into smaller parts.
Take this sentence:
The manager interviewed eight candidates, some of whom had worked for competing companies.
The phrase contains three important elements:
- Some refers to part of the larger group.
- Of is a preposition.
- Whom is the object of the preposition.
The sentence doesn’t mean that all eight candidates had worked for competing companies. It means a portion of those eight candidates had that experience.
You could rewrite it as:
The manager interviewed eight candidates. Some of them had worked for competing companies.
That version makes the grammatical relationship easier to see. Some of them becomes some of whom when the information is connected to the original noun through a relative clause.
A Simple Structural Pattern
The common pattern looks like this:
Main noun + , some of whom + verb or additional information
For example:
The company hired twenty employees, some of whom had previous management experience.
The phrase some of whom had previous management experience provides additional information about part of the twenty employees.
Why “Some of Who” Usually Doesn’t Work
The problem with some of who is that who doesn’t normally function as the object after of.
Compare these two sentences:
I met several researchers, some of who specialize in biology.
I met several researchers, some of whom specialize in biology.
The second sentence follows the standard preposition + object pattern.
Think about another familiar expression:
Some of them specialize in biology.
You wouldn’t normally say:
Some of they specialize in biology.
That’s because they is a subject form while them is an object form. The traditional who/whom distinction works similarly.
- they → them
- who → whom
So:
some of them → some of whom
This isn’t a perfect test for every use of who and whom, but it works very well for this particular construction.
Who vs. Whom: The Basic Rule
The traditional rule is straightforward.
Use “Who” for the Subject
Use who when the person performs the action.
Examples:
- The woman who called yesterday left a message.
- The students who studied passed the test.
- The employees who arrived early attended the meeting.
- The researcher who conducted the study published the results.
In each case, who performs the action.
The woman called.
The students studied.
The employees arrived.
The researcher conducted the study.
Use “Whom” for the Object
Use whom when the person receives the action or follows a preposition.
Examples:
- Whom did you invite?
- The person whom I contacted responded quickly.
- To whom should I send the documents?
- The professor, whom many students admired, retired last year.
In modern everyday English, many speakers use who instead of whom in some of these sentences. Still, whom remains standard in formal constructions such as some of whom.
How to Know When to Use “Some of Whom”
Use some of whom when all of these conditions generally apply:
- You’re referring to people.
- You’ve already mentioned a larger group.
- You’re talking about part of that group.
- The phrase introduces additional information about those people.
- The pronoun follows of.
For example:
The school invited thirty parents, some of whom volunteered for the event.
The larger group is thirty parents.
Only part of that group volunteered.
The phrase some of whom connects those volunteers to the original group.
More Examples
I know several writers, some of whom publish independently.
The conference attracted hundreds of visitors, some of whom traveled from overseas.
We interviewed five engineers, some of whom had worked on similar projects.
The restaurant employs twelve chefs, some of whom trained abroad.
She contacted several former classmates, some of whom still live nearby.
Each sentence uses some of whom to identify a portion of a previously mentioned group.
“Some of Whom” in Different Sentence Positions
The most common placement comes after a noun phrase and a comma. However, understanding the structure helps you recognize the phrase in longer sentences.
After a Comma
This is the classic pattern:
The company has more than 500 employees, some of whom work remotely.
The phrase adds information about some members of the group.
Another example:
The museum displayed dozens of paintings, some of which dated from the nineteenth century.
Here, which refers to paintings rather than people.
In a Longer Sentence
The phrase can appear inside a sentence containing several details:
The committee interviewed fifteen applicants for the position, some of whom had already completed advanced training in the field.
Although the sentence is longer, the grammatical structure remains simple:
fifteen applicants → some of whom → had completed advanced training
With Different Verb Tenses
The tense of the relative clause can change naturally:
We invited several speakers, some of whom have worked internationally.
We invited several speakers, some of whom had worked internationally.
We invited several speakers, some of whom will work on the project.
The expression some of whom stays the same. Only the verb changes according to the meaning.
“Some of Whom” vs. “Who”
This comparison causes a lot of confusion because who can absolutely be correct in sentences that mention some people.
Consider:
The employees who arrived early received coffee.
Here, who is the subject of arrived.
Now consider:
The employees, some of whom arrived early, received coffee.
Here, whom follows of.
The important difference isn’t simply whether the sentence talks about people. Both sentences do. The difference is the grammatical role of the pronoun.
| Sentence | Correct form | Why |
| The employees who arrived early received coffee. | Who | Who is the subject of “arrived.” |
| The employees, some of whom arrived early, received coffee. | Whom | Whom follows “of” as its object. |
| Some of the employees arrived early. | Neither | No relative pronoun is needed. |
| Some of them arrived early. | Them | Them is the object-form pronoun. |
This distinction is much more useful than simply memorizing a phrase.
Read More: Marquee vs Marquis – Meaning, Usage, Differences & Examples
“Some of Whom” vs. “Some of Them”
Both constructions are correct, but they create different sentence structures.
Compare:
I contacted several experts, some of whom recommended the book.
with:
I contacted several experts. Some of them recommended the book.
The meaning is nearly identical. The first version combines the ideas into one sentence. The second separates them.
When “Some of Whom” Works Better
Use some of whom when you want a smooth connection between the group and the additional information.
The organization has several advisors, some of whom have decades of industry experience.
This construction keeps the sentence compact.
When “Some of Them” Works Better
Use some of them when you want a simpler or more conversational rhythm.
The organization has several advisors. Some of them have decades of industry experience.
Neither version is inherently better. Your choice depends on the sentence and the tone you’re aiming for.
Can You Say “Some of Who” in Informal English?
You may occasionally encounter some of who in casual writing or speech. However, seeing a construction in actual usage doesn’t automatically make it the preferred form in standard English.
For formal writing, academic work, business communication, articles, reports, and edited prose, some of whom is the safer and grammatically standard choice.
If you find yourself uncomfortable using whom, you can often avoid the issue completely:
I interviewed several applicants. Some of them had previous experience.
That sentence sounds natural and doesn’t require you to make a who vs. whom decision.
Still, there’s no reason to avoid some of whom simply because whom can sound formal elsewhere. The phrase is well established in standard English.
Common Mistakes With “Some of Whom”
Mistake: Using “Some of Who”
Incorrect:
We hired ten workers, some of who had construction experience.
Correct:
We hired ten workers, some of whom had construction experience.
The word whom follows of.
Mistake: Dropping “Of”
Incorrect:
We hired ten workers, some who had construction experience.
This construction can sometimes be grammatical in a different context, but it doesn’t mean exactly the same thing as some of whom.
Compare:
Some who had construction experience applied.
Here, some who means some people who. The word who introduces a clause describing those people.
However:
We hired ten workers, some of whom had construction experience.
Here, the phrase means some members of the ten workers.
That small word of changes the structure.
Mistake: Confusing “Whom” With “Whose”
These words aren’t interchangeable.
The students, some of whom won awards, celebrated.
Here, whom refers to the students themselves.
But:
The students, some of whose projects won awards, celebrated.
Here, whose shows possession. Their projects won the awards.
The “He/Him” or “They/Them” Test
A quick substitution test can help you decide between who and whom.
Try replacing the pronoun with he or him.
- If he works → use who.
- If him works → use whom.
The same principle works with they/them.
Consider:
Some of ___ were teachers.
Try:
Some of them were teachers.
That sounds correct.
Therefore:
Some of whom were teachers.
Now consider:
___ called the office.
You could say:
They called the office.
Therefore:
Who called the office?
This method doesn’t solve every complicated pronoun question in English. However, it provides a practical shortcut for many everyday cases.
FAQs:
Is “some of whom” grammatically correct?
Yes. Some of whom is the standard grammatical construction when referring to part of a group of people. For example, “The company hired ten workers, some of whom had previous experience.”
Is “some of who” ever correct?
In standard English, some of who should generally be avoided. If you’re writing an article, academic paper, report, professional email, or other edited text, choose some of whom instead.
Why do we use “whom” after “of”?
Whom is traditionally the objective form of who. Because of functions as a preposition, the pronoun that follows it takes the object form. Therefore, some of whom follows the standard grammatical pattern.
Can I use “some of them” instead of “some of whom”?
Yes. Some of them is a correct alternative when the sentence structure allows it. For example, “I met several writers. Some of them live nearby.” This version usually requires a separate sentence.
Is “some of whom” too formal?
Not necessarily. It can sound polished and slightly formal, but it’s common in standard written English. If you want a more conversational style, you can often use some of them instead.
Conclusion:
The difference between some of whom vs. some of who becomes much easier once you stop treating it as a matter of spelling and look at the grammar underneath. Some of whom is the standard form. Use it when you’re referring to part of a previously mentioned group of people and whom functions as the object after of. Once that pattern becomes familiar, phrases such as some of whom, many of whom, several of whom, one of whom, and both of whom become much easier to use. The key is to look at the grammatical role rather than simply choosing the word that sounds more familiar.
