Checkup vs. Check-up vs. Check Up
For the medical-examination noun, Cambridge labels “checkup” as US English and “check-up” as UK English. The spaced words belong to the phrasal-verb construction “check up on,” which has a different grammatical role and meaning.
Use “checkup” in US English and “check-up” in UK English for the medical-examination noun. Use “check up” as part of the phrasal verb “check up on.”
Key details
Choose the right form
| If you mean / need | Use | Why |
|---|---|---|
| a medical-examination noun in US English | checkup | The US noun is closed. |
| the same medical-examination noun in UK English | check-up | The UK noun is hyphenated. |
| the phrasal verb used with “on” | check up | The verb is written as two words. |
Further guidance
Core difference
Use the noun or modifier form documented by the dictionaries when naming a thing, event, result, or concept; use the spaced form when the words function as a verb.
Fast Test
If the expression can take ordinary verb tense or inflection in the sentence, the spaced phrasal-verb form is usually the relevant form.
Variant Boundary
Cambridge explicitly distinguishes US “checkup” and UK “check-up” for the noun; the spaced form occurs in the phrasal verb “check up on.”
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- CHECKUP — English meaning (opens in a new tab)Cambridge Dictionary · US closed noun “checkup”; Cambridge identifies UK “check-up”
- CHECK UP ON SOMEONE — English meaning (opens in a new tab)Cambridge Dictionary · Two-word phrasal verb construction “check up on” for verifying or monitoring