Resource management is one of the foundational elements of successful project planning. When dealing with complex timelines, it becomes critical to account for the availability of each team member or resource. This is where resource calendars come into play in Microsoft Project 2021 Professional. These calendars ensure that your project schedule realistically reflects the working and non-working times of every resource, preventing scheduling conflicts and over-allocations.

In this comprehensive guide, we will explore how to set up, customize, and manage resource calendars in Microsoft Project 2021 Professional.

What Are Resource Calendars?

A resource calendar defines the specific working days and hours for a particular resource. Unlike the project or task calendar, which defines the working schedule for the entire project, a resource calendar allows for individual customization. For instance, if a team member is only available on Mondays, Wednesdays, and Fridays from 10:00 AM to 4:00 PM, a resource calendar can reflect that schedule precisely.

Types of Calendars in Microsoft Project:

  1. Base Calendar ā€“ Defines general working hours (e.g., Standard, 24 Hours, Night Shift)

  2. Project Calendar ā€“ The default calendar for the whole project

  3. Task Calendar ā€“ Overrides the project calendar for specific tasks

  4. Resource Calendar ā€“ Defines working times for specific people or equipment

Why Use Resource Calendars?

Using resource calendars allows project managers to:

  • Accurately assign availability of team members

  • Avoid overallocation and scheduling conflicts

  • Reflect real-world constraints such as part-time shifts, vacations, or maintenance windows

  • Improve resource forecasting and timeline accuracy

Step-by-Step: Creating Resource Calendars in Microsoft Project 2021 Professional

Letā€™s walk through the steps to create and apply resource calendars:

Step 1: Launch Microsoft Project 2021 Professional

Open your project file or create a new one in Microsoft Project 2021 Professional. Make sure your resource list is defined before creating individual calendars.

Step 2: Open the Resource Sheet

  1. Go to the View tab on the Ribbon.

  2. Click on Resource Sheet.

  3. Here you can view, add, or edit resources.

If your resource doesnā€™t yet exist, create one by entering a name under the ā€œResource Nameā€ column.

Step 3: Access Resource Information

  1. Right-click on the desired resource.

  2. Select Information.

  3. In the Resource Information dialog box, go to the General tab and locate the Base Calendar dropdown.

  4. Choose a base calendar (e.g., Standard) as a starting point.

  5. Click on the Change Working Time button to customize further.

Step 4: Customize Working Time for a Resource

In the Change Working Time dialog box:

  • Use the Calendar dropdown to make sure youā€™re editing the correct resource.

  • On the calendar grid, select specific dates you want to change (e.g., holidays, vacations).

  • Under Exceptions, you can:

    • Name the exception (e.g., Annual Leave)

    • Set Start and Finish dates

    • Add recurring exceptions (e.g., every Friday off)

To adjust daily working hours:

  1. Click on the Work Weeks tab.

  2. Click Details.

  3. Select days of the week.

  4. Choose Set day(s) to these specific working times, and input the custom times (e.g., 10:00 AM ā€“ 2:00 PM).

Click OK when done.

Step 5: Assign the Calendar to the Resource

The customized calendar is automatically linked to the resource. Once you have configured the working time, any task assigned to that resource will be scheduled according to their personal calendar, not just the default project calendar.

Using the Resource Calendar in Task Scheduling

When assigning resources to tasks:

  • Project will adjust task timing based on the resource’s availability.

  • If a task is assigned to multiple resources with different calendars, the task will follow the availability overlap (common working hours).

  • Task durations may be extended if a resource has limited working hours.

Tips for Managing Resource Calendars

1. Use Base Calendars for Groups

If several resources share the same schedule (e.g., night shift), create a custom base calendar and assign it to multiple resources to avoid duplication.

2. Label Exceptions Clearly

Use meaningful names for exceptions and work-week changes (e.g., “Training Week”, “Sick Leave”) to avoid confusion later.

3. Recheck Calendars Before Baseline

Always verify your resource calendars before setting your project baseline to ensure the initial plan reflects true availability.

4. Review Overallocations

After assigning tasks, check for overallocated resources:

  • Go to Resource Usage View

  • Look for red indicators next to resource names

  • Adjust assignments or update calendars accordingly

How to Create a Custom Base Calendar

  1. Go to Project > Change Working Time

  2. Click Create New Calendar

  3. Name it (e.g., ā€œMarketing Team Scheduleā€)

  4. Choose to create from an existing calendar (e.g., Standard)

  5. Modify as needed under the Work Weeks tab

  6. Assign it to appropriate resources under Resource Information

Exporting and Sharing Resource Calendars

Although you can’t directly export calendars, you can:

  • Use templates to replicate calendar setups across projects

  • Use the Organizer tool (File > Info > Organizer) to copy custom calendars between project files

Advanced Use: Linking Task and Resource Calendars

Sometimes you may want a specific task to run on a different schedule regardless of the resource calendar.

  1. Create a task calendar via Project > Change Working Time > Create New Calendar.

  2. Assign the calendar to a task via Task Information > Advanced tab > Calendar.

  3. Check Ignore Resource Calendars if the task must follow the task calendar strictly.

Common Scenarios and Solutions

Scenario Solution
Resource working part-time Adjust work weeks to reflect exact hours
National holiday or company-wide leave Add exception to base calendar
Night shift resources Create custom base calendar with night hours
Freelancers with unique schedules Customize individual resource calendars
Mismatched calendars causing delays Check task and resource calendar compatibility

Benefits of Using Resource Calendars

  • Improved Scheduling Accuracy: Prevents unrealistic task timing.

  • Better Resource Utilization: Avoids assigning tasks when resources are unavailable.

  • Project Transparency: Stakeholders see a more accurate project timeline.

  • Automation of Workflows: Reduces manual adjustments when resource availability changes.

FAQs

Q1: Can I create different calendars for different departments?
 Yes. You can create custom base calendars and assign them to each departmentā€™s resources.

Q2: What happens if I donā€™t use resource calendars?
 Project will assume the resource follows the default project calendar, which can cause conflicts if availability differs.

Q3: Can I copy a calendar from one project to another?
 Yes. Use the Organizer tool to copy calendars between project files.

Q4: How do I reflect vacations in a resource calendar?
 Use the Exceptions tab in the Change Working Time window and set non-working days.

Q5: Do task calendars override resource calendars?
 Only if you check ā€œIgnore resource calendarsā€ in the Task Information > Advanced tab.