Enquiry vs Investigation

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

Enquiry

Top 5,000 (fairly common)B2noun

Investigation

Top 2,000 (common)B2noun
Most common: Investigation
 EnquiryInvestigation
Pronunciation🇬🇧 /["/ɪnˈkwaɪəri/"]/🇺🇸 /["/ˈɪnkwəri//ɪnˈkwaɪəri/"]/🇬🇧 /["/ɪnˌvestɪˈɡeɪʃn/"]/🇺🇸 /["/ɪnˌvestɪˈɡeɪʃn/"]/
MeaningA question or a request for information.Looking into something to find out more about it.
ExampleI made an enquiry about the availability of the product.The police launched an investigation into the missing person's case.
RegisterNeutralNeutral
How commonTop 5,000 (fairly common)Top 2,000 (common)
CEFR levelB2B2
Part of speechnounnoun
Collocationsdetailed, thorough, full, carry out, conduct, have, be underway, take place, begin, report, team, process, at an/​the enquiry, during an/​the enquiry, in an/​the enquiry, a steward’s enquiry, the outcome of an enquiry, the result of an enquiry, exhaustive, extensive, thorough, flood, stream, make, pursue, send, desk, office, service, pending enquiry, enquiry about, enquiry as to, direct an enquiry to somebody, careful, systematic, further, encourage, enquiry concerning, enquiry into, an area of enquiry, a board of enquiry, a commission of enquirycareful, close, detailed, carry out, conduct, pursue, demonstrate something, reveal something, show something, on investigation, under investigation, investigation into, the subject of an investigation, careful, close, detailed, carry out, conduct, pursue, demonstrate something, reveal something, show something, on investigation, under investigation, investigation into, the subject of an investigation
Antonymsanswer, responsedisregard, neglect, overlook
Common mistakesConfused with 'inquiry'; 'enquiry' is often British English., Using 'enquiry' in informal contexts where 'question' is more suitable., Incorrect pluralization; 'enquiries' should not be replaced with 'enquiries'.Confused with 'invest' which means to put money into something., Using 'investigation' as a verb instead of a noun., Mixing up 'investigation' with 'inspector', which refers to a person.
Usage notesUse 'enquiry' in formal or business contexts when asking for information. In casual conversations, 'question' may be more common. Avoid using 'enquiry' in very informal settings.Use 'investigation' in formal contexts, like police work or research. Avoid in casual conversations.

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Investigation

Frequently asked questions: Enquiry vs Investigation

What's the difference between Enquiry and Investigation?

Enquiry: A question or a request for information. Investigation: Looking into something to find out more about it.

Which is more common: Enquiry and Investigation?

Investigation is the most common in everyday English.

Are Enquiry and Investigation the same CEFR level?

Enquiry: B2, Investigation: B2 on the CEFR scale.

What part of speech are Enquiry and Investigation?

Enquiry: noun, Investigation: noun.

Can you show an example of each?

Enquiry: I made an enquiry about the availability of the product. Investigation: The police launched an investigation into the missing person's case.

Can I use Enquiry and Investigation interchangeably?

Not always. Enquiry and Investigation 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.

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