Due date alert

Welcome to the forum.

There are instructions at the top of the page explaining how to attach your sample workbook.

A good sample workbook has just 10-20 rows of representative data that has been desensitised. It also has expected results mocked up, relevant cells highlighted and a few explanatory notes.

You can't easily do 'alerts' directly in Excel, without awkward use of VBA. Some other options are:

a) Use VBA to automatically generate calendar appointments in Outlook
b) Use conditional formatting in your excel spreadsheet to highlight upcoming/overdue assessments
c) Filter your spreadsheet for upcoming/overdue assessment.

At a starting point, you will want need three columns for each contact - one with 'date of last assessment', one with 'period between assessments' and another that calculates 'due date for next assessment' from the previous two columns.

Yes, you can if you create a formula in an adjacent cell or conditional formatting rule. This is why I would like to see the OP's workbook so that I can show them how.