FYI Capitalization and Punctuation
FYI/fyi abbreviates “for your information,” especially in messages and email. Cambridge records uppercase and lowercase forms, so capitalization should follow context or house style rather than a universal rule.
“FYI” means “for your information.” Cambridge records both FYI and fyi in business contexts, without internal periods.
Key details
Important caveats
Punctuation Boundary
The Cambridge forms are written without internal periods; sentence punctuation still follows ordinary syntax.
Further guidance
Capitalization
Cambridge Business English records “FYI” and “fyi.”
Meaning
FYI abbreviates “for your information” and is commonly used when passing along information someone should see or know.
Practical Application
Use “FYI” without internal periods when you need the abbreviation for “for your information.” Match capitalization to the surrounding business style, recognizing that lowercase “fyi” is also documented.
Reader Check
Does the abbreviation fit the tone, and are you using a consistent capitalization style without adding unnecessary internal periods?
Worked Example
Write “FYI, the venue has changed” in a brief internal message, or spell out the purpose in more formal copy when an abbreviation would be too abrupt.
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.
- FYI — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · FYI/fyi meaning and use in email/business communication