In project management, calendars determine when work can occur. In Microsoft Project, calendars define the working and non-working time for the schedule. You can create a variety of calendars within the program for different projects. You can even use multiple calendars within one single project for different types of tasks. Microsoft Project allows you to create a variety of calendars to show exactly when work will be performed and when it will not.
While Microsoft Project will provide several default calendars for use, you may need to create your own as well. You should create your desired calendar before adding tasks to the project. However, this is not imperative – you can always adjust the assigned project, task and resource calendars later on as needed.
This article will demonstrate how to create, edit, and assign calendars within Microsoft Project. The following examples are from Microsoft Project 2021 Professional. However, the process is the same for most versions of Project.
Types of Calendars Available in Microsoft Project
There are four types of calendars within Project: base, project, task, and resource.
Base calendars are generally default template calendars. By default, Project will provide three base calendars: Standard, 24 Hours, and Night Shift. The calendars are templates that are used to create other calendar types. It’s recommended to only use base calendars for generic work periods. For example, you could create a base calendar specifically for your company that includes your typical work and non-work times. You can then use this base calendar as a template to create additional calendars. Base calendars are used to create all other calendar types.
If you’re using the Project Web App, only administrators can adjust the base calendars.
Project calendars are base calendars that are customized for an individual project. When you create a new project in Microsoft Project, you will need to assign a project calendar. This calendar will determine the default working days and times for the entire project. Each task you add to the project will use the set project calendar, unless otherwise specified. For example, you may have a project with an assigned project calendar that works 4 days a week, 10 hours per day. By default, each task added to the project will be set to work 4 days a week, 10 hours a day based on this calendar.
You will need to assign all projects a project calendar. Like all calendars, project calendars are copies of base calendars adjusted for the specific project.
Task calendars are base calendars that are customized for an individual project task. By default, each task will use the assigned project calendar – but you can adjust the individual task calendars as well. Each task within the project can use a different calendar. For example, you may have a project with an assigned project calendar for 5 days a week, 8 hours a day. We need to add a new task for the curing of concrete forms. This task will work 24 hours a day, 7 days a week. You can adjust this individual task’s calendar to specify its specific working days and hours.
Task calendars copies of base calendars adjusted and assigned to specific project tasks.
Resource calendars are base calendars that are customized for individual resources. By default, each resource will be assigned the project calendar – but you can switch this to a specific resource calendar. Each resource within the project can use a different calendar. This is very important, as resources may have PTO or specific times they are unavailable to work. Adding these times to a resource calendar will make sure the resource can work the tasks they’re assigned.
Like project and task calendars, resource calendars are base calendars adjusted and assigned to specific resources.
Although these different types of calendars are utilized differently, they are all created the same way. The calendar type generally depends on how you assign the calendar within the project.
Creating a New Calendar in Microsoft Project
First, open up a project within Microsoft Project. To create a new calendar, we will need to access the Main Ribbon, which will only display with a project open. If you’re planning on creating a project calendar, open up the project you’ll be creating the calendar for.
Within the Main Ribbon, select Project > Change Working Time.
The Change Working Time window will open. Here, you can adjust the current calendars and create new ones. Under For calendar, you can see the 3 default calendars that come with the program:
Standard: This is a standard 8-hour workday calendar. This calendar is set to work from 8 AM to 5 PM with an hour-long lunch break at noon, Monday through Friday.
- Night shift: This calendar reflects a standard graveyard shift schedule. It has a working period of Monday night through Sunday morning: 11PM to 8AM with an hour-long lunch break from 3AM-4AM.
- 24 Hours: This calendar is set to work 24 hours a day, 7 days a week with no break period. This is generally used for activities that don’t require resources – such as an activity representing curing time.
In the Create New Base Calendar column, you can give your new calendar a name. I’ll name mine Standard Work (5×8), meaning 5 days a week, 8 hours a day. It’s a good scheduling practice to include the standard working hours and days in the name of the calendar. Then, you can choose to create a new base calendar, or copy one of the existing calendars to use as a template.
If you want to create a base calendar to use on multiple projects, make sure to select Create a new base calendar. If you want to create a project, task, or resource calendar for the open project, select Make a copy of and choose a base calendar to use as a template.
In this example, I’ll be creating a project calendar, so I’ll choose to make a copy of a base calendar and select Standard. Then, press OK.
Creating the Standard Work Week
Creating Additional Work Weeks
Now, we can adjust the working period for the Winter months by double clicking on Winter. Again, I’ll select Monday through Friday, select Set days to these specific working times and set the desired times – 8AM to 12PM, 1PM to 5PM. Then, press OK.
Adding Exceptions and Holidays
Working Time Exceptions
Assigning the Calendar
Assigning to a Project
Assigning to a Task
Assigning to a Resource
Reusing Base Calendars
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Lauren Hecker is an Oracle Primavera Cloud and Primavera P6 Instructor and teaches onsite and virtual scheduling courses. To see her next open enrollment course, please visit our calendar. To schedule an onsite or custom course, please contact us!