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 FileMaker Pro Custom Functions

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endDate(theDate; months)

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  Average rating: 4.8  (29 votes)
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Tim Brown, Antidote Solutions

Calc the end date based on number of months to preserve the day of month.

Sample Input:
endDate( 7/31/2010; 7)
Sample Output:

 Then copy & paste into FileMaker Advanced's Edit Custom Function window.


This solves the problem of alway billing an item on the same day each month. We capture for the days that may be the last day of the month.

If we always bill on the 30th of each month. Then when we get to February, it will calculate the 28th, instead of March 2nd. This calculation is different then the last day of the month, because it allows you to pick the day of the month to always repeat.

Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

This is my Custom Function and I want to edit it


Try verifying this for 28, 29, 30, 31 for various months, especially February. Also, check for leap years.

For these one must determine what to do such as if the date is the 31 but the last day of the chosen month is 28, 29 or 30.

A typical problem for EOM billing.

Jack Rodgers, Hollywood, FL
May 18, 2011 10:40am

Thanks for the test. Just updated the calc to consider the last days of the month.

Tim Brown, Garden City, NY
May 18, 2011 10:59am

Saved me a lot of time, thanks a lot

Carsten van Dyhr, Höör/Sweden
May 29, 2018 2:23am

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