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
| Meaning / situation | Construction | Decision |
|---|---|---|
| medical examination noun in US English | checkup | use the closed noun |
| medical examination noun in UK English | check-up | use the hyphenated noun |
| investigate or verify someone/something | check up on + object | use the phrasal verb construction |
Quick tests
Noun-or-verb test
Are you naming a medical examination?
If yes: Use “checkup” in US English or “check-up” in UK English.
If no: If you mean investigate or verify, use “check up on.”
Caveat: Do not turn the phrasal verb into the medical noun or vice versa.
Examples
I scheduled an annual checkup.
US noun spelling.
I scheduled an annual check-up.
UK noun spelling.
I will check up on the shipment tomorrow.
The phrasal verb remains open and takes “on.”
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