Check in or Check-in: Which Is Correct?

Updated 2026-10-12 · Which One Is Correct editorial team

Quick answer: You must choose between the two-word phrase and the hyphenated version based on how the word functions in your sentence. When acting as a verb, such as arriving at a location, use two separate words. However, when referring to the event or the specific desk where that action happens, the hyphenated form is the correct choice. This distinction helps avoid confusion in professional and casual writing alike.

The Short Answer

Check in (two words) is the verb used to describe the action of registering or arriving. Check-in (hyphenated) is the noun or adjective used for the event or the desk.

People often mix these up because the sounds are identical, and both appear frequently in travel contexts. One is an action you perform, while the other is the thing you experience or the place where it happens.

Side-by-Side Comparison

Form	Status	Use it when
check in	Verb	You are arriving or registering
check-in	Noun or Adjective	You refer to the event or desk
check-in	Noun or Adjective	You modify another noun like line or desk
check-in	Noun or Adjective	You refer to the time of arrival

Correct Example Sentences

Please check in at the front desk before boarding.
The check-in process usually takes about ten minutes.
We will check in with our guests every morning.
His check-in time is set for early Tuesday.
Do not forget to check in your luggage.
The check-in counter is located on the left.
Guests must check in by five PM to get a room key.
We are going to check in on the project later today.
A long line formed for the daily check-in.
Please check-in status shows as confirmed for your flight.

Common Mistakes and Fixes

The check in desk is open for business.: The check-in desk is open for business.
We need to check-in before leaving.: We need to check in before leaving.
I will check in my bag at the gate.: I will check in my bag at the gate.
The hotel check-in was very slow.: The hotel check-in was very slow.
Please check-in with the manager upon arrival.: Please check in with the manager upon arrival.
Their check in was delayed due to traffic.: Their check-in was delayed due to traffic.

A Quick Test You Can Use

Ask yourself what part of speech the word represents in your specific sentence. If it describes an action happening to someone, keep the words separate. If it names the event, the object, or describes another noun, use the hyphen to link them together.

Related Word Pairs

check out vs. check-out: Use two words for the action of leaving, and a hyphen for the event or time.
sign up vs. sign-up: Use two words for the action of registering, and a hyphen for the list or form.
log in vs. log-in: Use two words for the action of entering, and a hyphen for the page or screen.
take out vs. take-out: Use two words for the action of removing, and a hyphen for the food style.
log out vs. log-out: Use two words for the action of leaving, and a hyphen for the event or session.

Frequently Asked Questions

Why is there a difference between check in and check-in?

The difference exists because English grammar distinguishes between actions and the nouns that name them. You use the verb form without a hyphen when describing what someone is doing, but you add a hyphen when naming the event or the place where that action occurs.

When should I never use a hyphen with this word?

You should never use a hyphen when the word is functioning as a verb. If you can replace the word with another action word like register or arrive, the correct spelling is always two separate words without any punctuation connecting them.

Is checkin with one word ever correct?

No, the version with one single word without a hyphen is incorrect in standard English. You must always choose between the two-word verb form or the hyphenated noun form depending on the grammatical role in your sentence.

What is the rule for using check-in as an adjective?

When the word describes another noun, such as a line or desk, it must be hyphenated. This hyphen connects the word to the noun it modifies, creating a compound adjective that clearly defines the specific type of object being mentioned.