EOMONTH selects the final day of the target calendar month. It differs from EDATE, which shifts the starting day by months. As ONLYOFFICE documents a serial result, format its output as a date. Use 0 months for the containing month and negative offsets for earlier months in the independently modelled examples.

Month-end formulas are especially useful when months have 28, 29, 30, or 31 days. Unlike DATE(YEAR(A2),MONTH(A2)+1,1)-1 alternatives, EOMONTH expresses the month-end intention directly. These two formula families should be compared on a blank workbook before adopting in finance processes.

=EOMONTH(start_date, months)

The ONLYOFFICE function page is an unversioned English web reference. Required/optional designations above reflect the brackets in its displayed syntax; no undocumented default, error code or argument coercion is inferred. Official EOMONTH source, accessed 2026-10-11.

Open a blank worksheet and select any empty cell for the formula. Use the copy-ready examples below, entering a holiday into F2 where shown. Never enter the date text directly if the editor does not recognize its locale; use DATE(…) to construct it.

Copy any expression in Copy-ready formula to a result cell. If that row has a holiday, first enter the shown value into F2 using =DATE(year,month,day). When testing a new row, change F2 accordingly. Dates shown in the outcome column require date formatting for EDATE, EOMONTH and WORKDAY; NETWORKDAYS returns an integer. The listed results are independent Python predictions, not a record of ONLYOFFICE execution.

The accompanying CSV is a fixture of input dates and independently predicted output, not a file executed in ONLYOFFICE. The dates were calculated using Python’s datetime.date, calendar.monthrange and ordinary Monday–Friday looping; that separate mathematical implementation may differ in undocumented edge cases from ONLYOFFICE’s actual engine.

First formula to paste

=EOMONTH(DATE(2024,1,31),1)

Independent expected result: 2024-02-29. Paste this formula into an empty cell (no other input cells are needed for this first example), then format it as a date when applicable. This is a runnable test to perform in a native ONLYOFFICE editor; the outcome has not been observed there.

1. End of current month

=EOMONTH(DATE(2026,10,11),0)

Independent expected result: 2026-10-31. Fixed cutoff independent of the day within the month.

2. End of previous month

=EOMONTH(DATE(2026,10,11),-1)

Independent expected result: 2026-09-30. Useful when closing the September reporting period.

3. First of next month

=EOMONTH(DATE(2026,10,11),0)+1

Independent expected result: 2026-11-01. Serial arithmetic advances one day; predicted calendar display needs date formatting.

4. Quarterly closing date

=EOMONTH(DATE(2026,10,11),2)

Independent expected result: 2026-12-31. October plus two months reaches December, the Q4 close date.

If your workbook displays #VALUE!, #NUM!, or another result, do not ascribe a specific ONLYOFFICE exception rule to it without a reproducible native experiment: the concise function page does not establish detailed input coercion and errors. Preserve the exact input cell types and locale. A visually formatted date is not by itself proof that the stored value is a valid date.

EDATE shifts a date by a number of months; it is not a general month-end finder.

• EDATE — confirmed vendor reference; not a claim that a corresponding Spreadsheet-Tutorials.com tutorial is live.
• DATE — confirmed vendor reference; not a claim that a corresponding Spreadsheet-Tutorials.com tutorial is live.
• MONTH — confirmed vendor reference; not a claim that a corresponding Spreadsheet-Tutorials.com tutorial is live.

Cross-application compatibility: Microsoft Excel’s EOMONTH documentation gives the same English signature. Excel describes this same syntax, including numeric date serials. Excel explicitly truncates fractional offsets; that particular rule is not guaranteed by ONLYOFFICE’s short function page. Function availability and error semantics in Google Sheets, LibreOffice Calc and older workbook formats have not been experimentally checked here; don’t assert universal equivalence from the name alone.

These samples use the English formula names with commas and begin with =. ONLYOFFICE’s function entry guide explains its function picker and Formula tab, while the Advanced Settings guide documents Formula Language, Region, customizable numeric separators and the 1904 date system option. A machine configured for another language or regional syntax should use the editor’s function picker to confirm the correct localized formula; the short function references do not establish every locale’s argument separator. Use DATE(year,month,day) instead of ambiguous date strings and apply an explicit ISO-like date display to results.

Edition evidence (checked 2026-10-11): The official unversioned English ONLYOFFICE help page documents the named function but does not state its first-supported Desktop/Web/mobile build. ONLYOFFICE Docs 10.0 was announced 2026-10-10; the independent Desktop Editors changelog currently lists 9.4.0 released 2026-05-19. These release references establish two distinct version streams, not native function test coverage. Availability and behaviour in a specific build, mobile editor, workbook imported from Excel or old-format .xls file remain unverified. The 1904 option changes numeric date serials; avoid comparing raw serial integers across workbooks without first checking workbook settings.

How to verify a discrepancy in your edition

1. Write down the application (ONLYOFFICE Docs/web or Desktop), exact version/build, OS/browser, workbook date system and formula language.
2. Enter the numeric DATE fixtures shown here into a new workbook, not text parsed from a CSV locale.
3. Format date results as yyyy-mm-dd where available, while retaining a numeric-format copy if serial debugging is necessary.
4. Compare the displayed outcome against the independently expected column; an expected result is not a screenshot, observation or claim that the software actually produced it.
5. If any outcome differs, preserve both the formula and actual output and flag the guide for correction; do not publish the expected prediction as tested truth.

• ONLYOFFICE Spreadsheet Editor — function documentation
• EDATE
• DATE
• MONTH
• function entry guide
• Advanced Settings guide
• ONLYOFFICE Docs 10.0

Verification status: Official documentation checked; example outcomes were independently reasoned or arithmetically checked where applicable. Not executed in ONLYOFFICE Spreadsheet Editor.

• No genuine ONLYOFFICE Spreadsheet Editor screenshots are included; this guide does not use mock application images.