The ADDDAYS function adds a specified number of days to a given date.

You cannot use ADDDAYS on a date/time object that does not specify the day of the month because an error will occur.

ADDDAYS (single-date-expression, single-integer-expression)
ADDDAYS (any_date, number_of_days_to_add)
A single date

The ADDDAYS function returns the date, which results from adding number_of_days_to_add to any_date. If any_date has a presentation that does not contain a century, the century is determined based on the Century > CCLookup map setting (when the Century > Switch = ON), or the current century (when the Century > Switch = OFF).

When the year exceeds four digits, the output will display hash characters (#) for the CCYY values because the field is defined to be only four digits in length.


  • You can use the ADDDAYS function to increment a date by a fixed number of days, such as to calculate a DueDate that is always 30 days after the InvoiceDate.

    To produce a date in the output, such as a ship date, you might need to add a variable number of days to a date in the input. For example: ADDDAYS (PODate, LeadTime).

  • ADDDAYS (InvoiceDate, 10)

    Returns the date, which results from adding 10 days to the value of InvoiceDate.

  • ADDDAYS (InvoiceDate, DaysTilDue)

    Returns the date that results from adding the value of DaysTilDue to the InvoiceDate value.

  • ADDDAYS (TODATETIME ("000101"), -1)

    Returns 991231

  • ADDDAYS (TODATETIME ("20000101"), 1)

    Returns 20000102

  • ADDDAYS (TODATETIME ("10/20/1996", "{MM/DD/CCYY}"), 5)

    Returns 10/25/1996

    In the examples containing TODATETIME, the text literal is first converted to a date, and then the specified number of days is added to that date.

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