Excel
EOMONTH function in Excel
Returns the serial number of the last day of the month before or after a specified number of months
=EOMONTH(start_date, months)EOMONTH syntax and parameters
Two arguments, two required.
- start_dateanyRequired
- monthsnumberRequired
EOMONTH examples
Formulas you'll actually reuse.
The last day of the invoice's month — month-end close:
=EOMONTH(B2, 0)Result
2026-08-31The first day of the same month — end of last month, plus one:
=EOMONTH(B2, -1) + 1Result
2026-08-01
EOMONTH in Google Sheets
Same name — your formula ports as-is.
Try EOMONTH in the playground
Edit the example — nothing to install.
Preloaded with the EOMONTH formula from Example 1 — change anything and watch it respond.
Loading the editor…
Related functions
More ways Excel gets this done.
- DATEReturns the serial number of a particular dateDateGoogle Sheets
- DATEDIFCalculates the number of days, months, or years between two dates. This function is useful in formulas where you need to calculate an age.DateGoogle Sheets
- DATEVALUEConverts a date in the form of text to a serial numberDateGoogle Sheets
- DAYConverts a serial number to a day of the monthDateGoogle Sheets
- DAYSReturns the number of days between two datesDateGoogle Sheets
- DAYS360Calculates the number of days between two dates based on a 360-day yearDateGoogle Sheets