Calendar Year vs. Fiscal Year
A calendar year runs from January through December, while a fiscal year is an organization’s accounting or reporting year and can use a different twelve-month span. In writing, clarify which year basis a period label refers to when dates or comparisons could be misunderstood.
Use calendar year for January–December and fiscal year for an organization’s reporting year; state the fiscal-year dates or convention when they do not match the calendar year.
Key details
Important caveats
Clarity Boundary
When a fiscal year does not align with January–December, state or define its boundaries so year labels are interpretable.
Meaning Boundary
This page compares the periods themselves; the existing Fiscal Year Formatting guide owns label forms such as FY25 versus FY 2025.
Further guidance
Practical Application
Use “calendar year” for January through December. Use “fiscal year” for an organization’s accounting/reporting year, and state the date span or local FY convention whenever it could be ambiguous. Keep comparisons on the same year basis unless you explicitly explain the mismatch.
Reader Check
Would a reader know the exact start and end dates behind the year label and whether both compared periods use the same basis?
Worked Example
Write “FY2026 (1 July 2025–30 June 2026)” when that is the organization’s reporting year instead of assuming readers will interpret FY2026 as January–December 2026.
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.
- Fiscal Year (FY) — 12 Month Accounting and Reporting Period (opens in a new tab)Corporate Finance Institute · Definition and reporting-period boundary for fiscal years