For whom vs To who

When to use each in English, with meaning, register, and examples.

For whom

FormalBeyond 10,000 (less common)

To who

Beyond 10,000 (less common)
Most formal: For whom
 For whomTo who
Pronunciation🇬🇧 //fɔːr huːm//🇺🇸 //fɔr hum//🇬🇧 //tʊ huː//🇺🇸 //tu hu//
MeaningWho is the action intended for?A phrase used to ask about a person or people.
ExampleThis gift is for whom it may concern.I asked to who I should send the invitation.
RegisterFormalNeutral
How commonBeyond 10,000 (less common)Beyond 10,000 (less common)
Collocationsfor whom it may concern, for whom are you waiting, for whom is this bookto who it may concern, to who does this belong, ask to who
Common mistakesIncorrectly using 'who' instead of 'whom' when it's the object of a preposition., Confusing the phrase with 'for who', which is grammatically incorrect., Not using it in appropriate formal contexts.'To who' is often confused with 'to whom', especially in formal contexts., Some learners forget to use 'to' in the phrase., Misplaced word order in questions using 'to who'.
Usage notesUsed in formal or literary contexts to inquire about the beneficiary of an action. Less common in everyday conversation.Use 'to who' when directly addressing someone. It's less formal. Use 'to whom' for formal writing or speeches.

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For whom
To who

Frequently asked questions: For whom vs To who

What's the difference between For whom and To who?

For whom: Who is the action intended for? To who: A phrase used to ask about a person or people.

Which is more formal: For whom and To who?

For whom is the most formal of these.

Can you show an example of each?

For whom: This gift is for whom it may concern. To who: I asked to who I should send the invitation.

Can I use For whom and To who interchangeably?

Not always. For whom and To who are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.