Calculating National and Religious Holidays for Your Project Schedule

In November, 2014 I started an annual tradition: I compiled a list of accepted national and religious holidays for the coming calendar year, and suggested that these holidays observed by the project team be considered non-working work days in the project schedules for the coming year. But it’s time to remove myself from the equation: I have prepared an Excel workbook that will calculate my list of national and religious holidays (now expanded), from 2021 to 2030.

Many holidays take place coming specific Date, such as Canada Day. Organizations that hold these holidays usually have their own rules on which day to take off when they occur on the weekend, so except for US Independence Day and Christmas, I do not try to predict if Friday or Monday will be non-working. Other holidays are based on Relative dates same as The third Monday of January, Like Martin Luther King’s birthday. In some cases the authorities have added wrinkle, such as Last Monday in August. Others are based on a Lunar calendar; Instead of trying to calculate the lunar Rosh Hashanah or Passover, I created a search table and populated it by 2030.

Download the workbook using the link at the bottom of this page. Next, enter the year you want to schedule in the cell at the top of the Holidays tab, marked in orange.

Change working time in MS Project

Navigation depends on which version of the project you are using. In Microsoft Project 2007, on the Tools menu, select Change work time. In Project 2010 or later, on the Project tab, select Change work time. You can then enter the holidays in the Exceptions tab. Note that unusual days appear in the calendar in blue; However, if you selected one of the exception dates, as shown in the example below, the date will appear in red. Unscheduled workdays appear in gray. Note that you can also make an exception from a set day without a job, so it will look like it is a work day. Use this feature carefully – after Some From the staff working over the weekend can easily cancel the planned for the whole staff.

Create a custom calendar

You can also create custom calendars, if your team is spread across several countries with different holidays. Again, the version of Microsoft Project you are using makes a difference in navigation. In the 2007 project, under e dishes Menu, select Change working time. In the 2010 project or later, on project Tab, select Change working time. Press on Create a new calendar Button in the upper left corner. Give the new calendar a meaningful name, and then click Make a copy of Radio button. Select the standard Calendar from the drop-down list. Then click OK.

At this point, you can add the dates that you want to mark as exceptions to the current calendar. Enter the name, start and end dates. Then click the Details button. Click the ‘Working Hours’ radio button. The default working hours will appear; Modify them only if necessary.

Click OK to return to your custom calendar and enter the inactive dates that apply. Then assign each team member to the appropriate calendar using the resource sheet, in the column labeled Base.

While it may be helpful to allow MS Project to reschedule automatically after making a change, be aware of what can happen when you have a summary task that includes team members who use different logs. Changing a one-day task to one particular can cause the task summary end date to change by two days or more. Check the results before you publish them, and investigate anything that seems wrong.

Once your career has progressed beyond managing several people placed together in one dice farm, your ability to think globally and manage a geographically distributed team will be the key to how far you can go. Develop your multicultural knowledge, awareness and communication skills, and when someone is required to manage a cross-border project, be prepared.


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Calculate national and religious holidays for your project schedule


I have prepared an Excel workbook that will calculate the common national and religious holidays, from 2021 to 2030.


Dave Gordon

IT Project Manager Trainee LLC




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