WORKDAY
The result is a date number that can be formatted as a date. You then see the date of a day that is a certain number of workdays away from the start date.
WORKDAY(StartDate; Days; Holidays)
StartDate is the date from when the calculation is carried out. If the start date is a workday, the day is included in the calculation.
Days is the number of workdays. Positive value for a result after the start date, negative value for a result before the start date.
Holidays is a list of optional holidays. These are non-working days. Enter a cell range in which the holidays are listed individually.
What date came 17 workdays after 1 December 2001? Enter the start date "2001-12-01" in C3 and the number of workdays in D3. Cells F3 to J3 contain the following Christmas and New Year holidays: "2001-12-24", "2001-12-25", "2001-12-26", "2001-12-31", "2002-01-01".
=WORKDAY(C3;D3;F3:J3) returns 2001-12-28. Format the serial date number as a date, for example in the format YYYY-MM-DD.