Returns the difference between two days based on the 360-day year used in some financial interest calculations.

Sample Usage



DAYS360(start_date, end_date, [method])

  • start_date - The start date to consider in the calculation.
  • end_date - The end date to consider in the calculation.
  • method - [OPTIONAL] A logical value that specifies whether to use the U.S. or European method in the calculation.



DAYS360(DATE(2011,1,30),DATE(2011,2,1)) returns 1.


  • Ensure that the date inputs to the function are either references to cells containing dates or functions which return date objects.
  • A method value of 1 implies the US method. Under this method, if start_date is the last day of a month, the day of month of start_date is changed to 30 for the purposes of the calculation. Furthermore if end_date is the last day of a month and the day of the month of start_date is earlier than the 30th, the end_date is changed to the first day of the month following end_date, otherwise the day of month of end_date is changed to 30.
  • A method value of 2 implies the European method, where any start_date or end_date that falls on the 31st of a month has its day of month changed to 30.