EOMONTH
Returns the date of the last day of a month which falls months away from the start date.
This function is part of the Open Document Format for Office Applications (OpenDocument) standard Version 1.2. (ISO/IEC 26300:2-2015)
Syntax
EOMONTH(StartDate; Months)
StartDate is a date (the starting point of the calculation).
Months is the number of months before (negative) or after (positive) the start date.
Example
What is the last day of the month that falls 6 months after 14th September 2001?
=EOMONTH(DATE(2001;9;14);6) returns the serial number 37346. Formatted as a date, this is 2002-03-31.
=EOMONTH("2001-09-14";6) works as well. If you specify the date directly, we recommend using the standard ISO 8601 format because this should be independent of your selected locale settings.