How to get the quarter-end date for any date
✓ Verified in LibreOffice 25.8.7.3Snap a date to its quarter's last day — reporting cutoffs, fiscal deadlines.
The formula
| App | Formula | Notes |
|---|---|---|
| Excel | =EOMONTH(DATE(YEAR(A2),CEILING(MONTH(A2)/3,1)*3,1),0) | CEILING(month/3)*3 finds the quarter's last month; EOMONTH finds its last day. |
| Google Sheets | =EOMONTH(DATE(YEAR(A2),CEILING(MONTH(A2)/3,1)*3,1),0) | Identical. |
| LibreOffice Calc | =EOMONTH(DATE(YEAR(A2),CEILING(MONTH(A2)/3,1)*3,1),0) | Identical. |
How it works
Month 7 divided by 3 and ceiled gives quarter 3; times 3 gives its closing month (September); EOMONTH lands on the 30th. The quarter-START date is the same construction minus two months: DATE(YEAR(A2),CEILING(MONTH(A2)/3,1)*3-2,1). For fiscal years that don't start in January, shift the month first with MOD before the arithmetic — or add a helper column, which everyone can read.
Verified, not just documented
We ran =TEXT(EOMONTH(DATE(2026,CEILING(MONTH(DATE(2026,7,26))/3,1)*3,1),0),"YYYY-MM-DD") in LibreOffice 25.8.7.3 (headless, with forced recalculation) and it returned 2026-09-30 — exactly the expected result. Every formula here is confirmed by actually executing it.