Writing & StyleStyle guide
ROI Meaning and Plural
ROI means “return on investment.” Cambridge marks ROI as both countable and uncountable, so singular/mass “ROI” and plural “ROIs” depend on whether the writer means the concept/measure generally or several distinct returns or figures.
ROI means “return on investment.” Use “ROI” for the concept or a single measure; “ROIs” is available when referring to several distinct return-on-investment figures or instances.
Key details
Core IssueROI means “return on investment” and Cambridge marks the abbreviation as countable or uncountable depending on context.
Phrase Rolefinance abbreviation
Registerprofessional, finance, and business writing
Important caveats
Plural Boundary
Because ROI is documented as countable or uncountable, use “ROIs” only when the context truly refers to multiple distinct ROI figures or instances.
Further guidance
Meaning
ROI expands to “return on investment.”
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.
- ROI — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · ROI meaning “return on investment” and countable/uncountable noun status