Sign-off vs. Sign Off
“Sign-off” is the noun for an ending or approval/authorization, while “sign off” is the phrasal verb. Collins also records closed “signoff” as an American noun variant, so the guide preserves that variant rather than treating it as universally wrong.
Use “sign-off” as the noun for an act of ending, approval, or authorization; Collins also records “signoff” as an American noun variant. Use “sign off” as the phrasal verb.
Key details
Choose the right form
| Meaning / situation | Form / construction | Decision |
|---|---|---|
| an act, instance, time, approval, or ending functioning as a noun | sign-off | Use “sign-off” for the documented noun use. |
| the action functioning as a verb | sign off | Use the two-word phrasal verb “sign off.” |
| a context where another documented noun spelling is explicitly established | follow the documented variant where applicable | “Signoff” is also recorded as an American noun variant; this guide does not erase that variant. |
Quick tests
Meaning / construction test
Is the expression functioning as a verb?
If yes: Use “sign off.”
If no: Use “sign-off” for the documented noun use.
Caveat: “Signoff” is also recorded as an American noun variant; this guide does not erase that variant.
Examples
Please sign off before entering the secure area.
“sign off” functions as a phrasal verb.
The sign-off took less than a minute.
“sign-off” functions as a noun.
They recorded the sign-off time in the log.
The hyphenated form functions as a noun modifier in this context.
Further guidance
Core difference
Use the documented noun/adjective form for the thing, result, event, or modifier; use the spaced form when the expression functions as a verb or predicate.
Fast Test
Ask what job the expression is doing in the sentence. A noun/adjective form may be closed or hyphenated by dictionary convention; a verb or predicate normally keeps the words separate.
Variant Boundary
Collins records the noun “sign-off” and an American “signoff” variant; Cambridge records the verb “sign off.”
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.
- Sign off — Collins English Dictionary (opens in a new tab)Collins English Dictionary · Hyphenated noun “sign-off” and its approval/ending senses
- Sign off — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Two-word phrasal verb “sign off” for ending communication/work and formal approval in “sign off on”