Calculating my own start and finish dates, removing holidays and weekends

I am building a sheet in the middle of a project, I would like to calculate my own start and finish dates, removing weekends and holiday. I've tried everything, is there a way to do this?


  • Ramzi K
    Ramzi K ✭✭✭✭✭

    If you don't want to use the Project Sheets' built in capabilities then try using the following formulas on your dates to filter out certain dates:

    WEEKDAY function where 1 = Sunday and 7 = Saturday

    For holidays, you will need a separate sheet with a column with holidays and then use that for filtering out days from your calculations (a bit tricky but can be done).

    Ramzi Khuri - Principal Consultant @ Cedar Tree Consulting (

    Feel free to email me: [email protected]

    💡 If this post helped you out, please help the Community by marking it as the accepted answer/helpful.

  • Thanks for your reply! :)

    I am using Project sheets built in capabilities for the baseline start and finish, however I also need to calculate my own start and finish dates in order to track delayed tasks (using predecessors and excluding nonworking days).

    I do not want to alter the baseline dates, ideally, if a project is delayed I would like to hard key over my start and finish dates and have the remaining tasks auto populate.

    I'm going to try my best to make sense of what I'm currently working on...

    Start column =WORKDAY(Finish47, [num_days]@row, Holidays:Holidays) + 1

    • Finish47 = I linked the finish date of the row predecessor
    • num_days is an additional column I added to manually update with 1 when the project starts on a weekend (I have an another column that utilizes your suggested WEEKDAY function where 1 = Sunday and 7 = Saturday formula that indicated when I have to update the num_days column

    Any suggestions on how to combine so I don't need the additional columns and have to do all this manual work each time a task is delayed?

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