Ongoing vs. On-going
For the adjective meaning continuing to exist, develop, or happen, Cambridge lists “ongoing” as one word. This guide therefore uses the closed form as the default for ordinary modern prose while keeping house-style exceptions separate from the lexical rule.
Use “ongoing” as one word in ordinary prose: “an ongoing investigation.”
Key details
Choose the right form
| Form | Status | Use |
|---|---|---|
| ongoing | modern dictionary form | Use as the default adjective for something continuing to happen or develop. |
| on-going | nondefault in ordinary modern prose | Preserve only when a required house style, historical quotation, or official form uses it. |
| on going | separate words in another grammatical construction | Do not substitute it for the adjective “ongoing.” |
Quick tests
Compound test
Do you mean “continuing to happen, exist, or develop”?
If yes: Use the closed adjective “ongoing.”
If no: Check whether “on” and “going” belong to a different grammatical construction.
Caveat: Official names and quoted text can preserve their original spelling.
Examples
The investigation is ongoing.
The closed form is the standard adjective.
We discussed the on-going investigation.
Better: We discussed the ongoing investigation.
Use the modern dictionary form “ongoing” in ordinary prose.
Further guidance
Boundary
A quoted historical spelling or organization-specific house style can be preserved without changing the default modern dictionary form.
Examples
Natural patterns include “ongoing investigation,” “ongoing process,” and “negotiations are ongoing.”
Form
Cambridge lists the adjective as “ongoing.”
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.
- Ongoing — English meaning (opens in a new tab)Cambridge University Press · Dictionary record for ongoing as one word