Checkup and check up use the same words — but the spacing changes everything. Checkup (one word) is a noun, while check up (two words) is a verb phrase.
The simple rule: you check up on someone’s health by scheduling a checkup. One is the action. The other is the appointment.
This guide breaks down the difference between checkup and check up, when to use each, and how the hyphenated form fits in.
What Does Checkup Mean?
Checkup (one word) is a noun — referring to a routine examination, screening, or inspection performed to evaluate health, condition, or status. It describes the event or appointment itself.
Example: “I have my annual dental checkup this afternoon.”
Common Uses of “Checkup”
As an adjective: Checkup can also modify another noun — describing something related to or associated with a checkup:
- “She filled out the checkup form at the front desk.”
- “His checkup results came back completely normal.”
Synonyms: physical, examination, screening, evaluation, inspection, assessment
What Does “Check Up” Mean?
Check up (two words) is a phrasal verb — describing the act of monitoring, investigating, or inquiring about the condition or wellbeing of someone or something. It is almost always followed by “on.”
Example: “She called to check up on her elderly neighbor after the storm.”
Common Uses of “Check Up”
Common Forms of “Check Up On”
What About “Check-Up” (Hyphenated)?
Check-up (with a hyphen) is an older variant that was historically used as the noun form. In modern writing, it has largely been replaced by the single-word checkup — which most current style guides prefer.
The hyphenated form occasionally still appears:
- In some British English writing
- In older published texts
- When used as a compound modifier before a noun: “a check-up appointment”
However, in virtually all modern American English contexts — and increasingly in British English too — checkup (no hyphen) is the preferred and accepted noun spelling.
The Core Rule — Noun vs Verb
The entire distinction comes down to part of speech:
A quick test: can you replace the word with “examination” or “appointment”? If yes → checkup (noun). Can you replace it with “monitor” or “inquire about”? If yes → check up (verb phrase).
Checkup vs Check Up – Side-by-Side Comparison
When to Use Checkup vs Check Up
Use “Checkup” (Noun) When:
- Referring to a scheduled examination or inspection
- Describing the appointment itself — not the action
- Using it as a modifier before another noun
Examples:
- “The pediatrician recommends annual checkups through adolescence.”
- “Her six-month checkup revealed no new concerns.”
Use “Check Up” (Verb Phrase) When:
- Describing the action of monitoring or inquiring about someone or something
- Almost always followed by “on”
- The sentence involves someone performing the action of checking
Examples:
- “I’ll swing by to check up on you this evening.”
- “The supervisor checks up on the team’s progress weekly.”
Common Mistakes to Avoid
Memory trick:
- Checkup → one thing → one word → the appointment or examination
- Check up → action in motion → two words → what you do before or after the appointment
- “You check up on your health by getting a checkup.” — both in the same sentence, used correctly
FAQs — Checkup or Check Up
Is it check up or checkup or check-up?
It depends on the grammatical role. Checkup (one word) is the noun — the examination or inspection. Check up (two words) is the phrasal verb — the act of monitoring or inquiring. Check-up (hyphenated) is an older, now largely outdated alternative for the noun form.
Is it correct to say “I called to check up on you”?
Yes — “check up on you” is completely correct. Check up on is a standard phrasal verb meaning to inquire about or monitor someone’s wellbeing. It is natural, grammatically sound, and widely used in everyday speech and informal writing.
Is check up all one word?
No — “check up” as a verb is two words. Only the noun form is written as one word: checkup. Combining them into “checkup” when you mean the verb action is a common but incorrect usage.
What does checkup mean?
A checkup is a routine examination or inspection — typically medical, dental, veterinary, or mechanical — designed to evaluate health or condition and identify any issues before they become serious. Example: “An annual checkup is one of the simplest things you can do for your long-term health.”
Conclusion
Checkup and check up work together — one describes the event, the other describes the action. Checkup (one word) is the noun — the appointment, the examination, the inspection itself. Check up (two words) is the phrasal verb — what you do when you monitor, inquire about, or verify someone’s condition.
Remember: you check up on someone’s health by getting a checkup. The space makes all the difference between a noun and a verb — and once you see that pattern, you will never confuse these two forms again.
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