Inquiry or enquiry, inquire or enquire: US and UK usage

Inquire and enquire both mean to ask, and inquiry and enquiry both mean a question or an investigation. American English uses the in- spellings for everything. British English often splits them: enquire and enquiry for everyday questions, inquire and inquiry for formal investigations, such as a public inquiry. The memory trick: e for everyday questions, i for investigations, and in America, i for everything.

Side by side, a routine request and a formal investigation look like this. In American English: I'm writing to inquire about the apartment and The city has opened an inquiry into the fire. In British English that follows the split: I'm writing to enquire about the flat and The council has opened an inquiry into the fire. Only the routine request changes its spelling.

The British split is a tendency, not a rule. The Oxford Learner's Dictionaries describe it and then add: “However, you can use either spelling in either meaning.” What matters is choosing one system and keeping it, which is harder than it sounds in a document full of contact details, customer emails and references to official reports.

Inquire vs enquire at a glance

What inquire and inquiry mean

Whichever spelling you use, the verb has two jobs. Merriam-Webster defines it as “to put a question” or “seek for information by questioning,” and also as “to make investigation,” often followed by into. The Oxford Learner's Dictionaries label the asking sense “rather formal,” which is worth remembering: in most sentences, plain ask does the job better. The common patterns:

• inquire about something: I'm writing to inquire about the vacancy.
• inquire into something, meaning investigate: The committee will inquire into the delays.
• inquire after someone, meaning ask how they are: She inquired after your mother.
• inquire of someone, formal for ask someone: He inquired of the clerk whether the court was sitting.
• inquire + a question, formal: “Is the train late?” she inquired.

The noun covers three senses in Merriam-Webster: “a request for information,” “a systematic investigation often of a matter of public interest,” and “examination into facts or principles : research,” the sense in scientific inquiry and lines of inquiry. The related forms follow the same spelling as the base word: inquirer or enquirer, an inquiring mind or an enquiring mind.

Inquiry has two accepted pronunciations, and dictionaries on both sides of the Atlantic list both: in-KWIRE-ee, with the stress on the second syllable, and IN-kwuh-ree, with the stress on the first. The spelling doesn't change either one.

The British split in practice

In British writing, enquiry tends to belong to the front desk and inquiry to the hearing room. You will see:

• Enquiries for everyday questions: For all enquiries, call the box office; directory enquiries, the telephone number service; and enquiries as the name of an information desk, as in the Oxford example Ask at enquiries to see if your bag has been handed in.
• A police phrase: someone “helping police with their enquiries,” which Oxford explains as being questioned but not charged.
• Inquiries for official investigations: UK public inquiries can be set up under the Inquiries Act 2005, whose first section is headed “Power to establish inquiry,” and the national investigation into the pandemic is the UK Covid-19 Inquiry.

The split is a tendency, and Oxford's own examples show it. Its entry for enquiry offers a murder enquiry and a public enquiry into the environmental effects of the proposed new road; its entry for inquiry offers the same phrases with an i. If a British house style simply says inquiry everywhere, it is following a pattern Oxford accepts.

American usage: inquire for everything

Merriam-Webster enters enquire, enquirer and enquiry only as “chiefly British spellings” of the in- forms, and Oxford notes that in American English inquire is usually used for both meanings. A customer inquiry, a congressional inquiry and a newspaper called The Philadelphia Inquirer all take the same letter. The habit is old.

Examples in sentences

American English, inquire and inquiry for both senses:

1. Several readers called to inquire about the missing chapter.
2. The agency received 400 inquiries in the first week.
3. The board launched an inquiry into the missing funds.
4. Her research begins as a historical inquiry and ends as a memoir.
5. The reporter inquired whether the mayor had seen the memo.

British English, the common split:

6. Please send all press enquiries to the communications team.
7. I'm enquiring about the flat advertised on Tuesday.
8. The minister announced a public inquiry into the fire.
9. The inquiry heard evidence from forty witnesses.
10. Thanks for your enquiry; we'll reply within two working days.

The phrasal patterns:

11. He always inquires after my grandmother.
12. The panel will inquire into how the contract was awarded.
13. She inquired of the porter where the archive was kept.
14. We inquired about late check-out and got it.

Both senses in one sentence:

15. (UK) The inquiry team answers enquiries from the public by email.
16. (US) The inquiry team answers inquiries from the public by email.

Common inquiry and enquiry mistakes

• Mixing systems: Send enquiries to the press office; our inquiry line opens at nine. → Pick one: enquiries and enquiry line, or inquiries and inquiry line.
• We welcome your enquiry in an American document → inquiry
• Thank you for your inquire. → inquiry (the noun has a -y)
• I would like to enquiry about prices. → enquire (the verb has no -y)
• She inquired to the manager. → inquired of the manager, or asked the manager
• Changing a name: the UK Covid-19 Enquiry → the UK Covid-19 Inquiry, as published

One more, which is a style problem rather than an error: inquire where ask would do. I am inquiring as to whether the invoice was received says less, more slowly, than Did the invoice arrive? The professional email examples show how much shorter a direct question usually is.

Quick quiz: inquiry or enquiry?

Fill each gap for the variety shown, then check the answers.

1. (US) Thank you for your ____ about our courses.
2. (UK, split) The hotel received dozens of ____ about the wedding venue.
3. (UK, split) The judge-led ____ will publish its report in spring.
4. (US) I'm calling to ____ about my order.
5. (Any) The committee was set up to ____ into the collapse.
6. (UK, split) Ask at the ____ desk on the ground floor.
7. (US) Scientific ____ depends on doubt.
8. (Any) The name of the 2005 UK law: the ____ Act.

Pick a convention and hold it

Business writing is where the two spellings collide: a contact page that says enquiries, a report that cites a public inquiry, an email template drafted by a colleague in Boston. Write your convention on the style sheet first, in one line: US: inquiry throughout, or UK: enquiry for questions, inquiry for investigations.

Then attach the style sheet to a chat with the Strokes Assistant and ask it to review the document for spellings that don't follow your rule. Decide the ambiguous ones yourself: the inquiry was passed to the committee could be a question or an investigation.

The same approach works for the other audience-dependent pairs, such as among and amongst and well-being and wellbeing.

Where the two spellings came from

English borrowed the word around 1300 from French. Merriam-Webster traces inquire to the Middle English enquiren, from the Anglo-French enquerre, from the Latin inquirere, built from in- and quaerere, “to seek.” So the en- spelling is the one English started with. According to Etymonline, the word was respelled in the 14th century on the Latin model, and the half-Latinized enquire persisted alongside it.

American English eventually settled on the Latin spelling for everything. British English kept both and, for many writers, gave them different jobs. Neither variety treats the other's spelling as a misspelling; the difference is one of habit and house style.