In Microsoft Project, there are two different scheduling modes available: Manual and Automatic. By default, the program will schedule new tasks manually – but you can adjust the scheduling mode to work automatically if desired. For newer schedulers, it may be difficult to know which mode of scheduling to use. Sometimes, the use of one mode over the other can lead to further issues, like rejected baselines. For each activity within your project, you can switch between these two scheduling modes – but typically, you’ll want to use just one mode for the entire project. Although Manual Scheduling is the default, you should not use it in all circumstances. In fact, for most contract schedules, you should always use Automatic Scheduling.

To ensure that you’re scheduling your tasks correctly, this article will look at how both Manual Scheduling and Automatic Scheduling works within Microsoft Project. Then, we’ll cover why you should use Automatic Scheduling for most projects. Lastly, we’ll go over how to adjust the project settings to use Automatic Scheduling as the default for new activities.

The following examples are from Microsoft Project Online Desktop Client (Version 2506). However, these tools are available in all versions of Microsoft Project – including Microsoft Project Online.

What is Manual Scheduling?

Manual Scheduling is the default scheduling mode in Microsoft Project. When you first create a project, all tasks will be manually scheduled – as shown in the lower left hand corner of the screen.

Manually scheduled tasks are those that you set dates for. You get to choose when each of these tasks should start within the schedule. This method of scheduling does not follow any scheduling principles or rules – like the Critical Path Method of Scheduling. Instead, it lets you decide when each activity will take place, regardless of other aspects in the project, like relationships. This method of scheduling gives you more flexibility, letting you plan tasks to occur at any time. However, Manual Scheduling typically takes more work – especially if you’re trying to be realistic. You’ll need to consider when each activity should start to ensure that all work gets done on time.

Manually scheduled tasks will display with a thumbtack icon by default – indicating that you’re pinning them to a spot in the schedule. For these tasks, the Duration, Start, and Finish fields will be blank by default – and you can leave them blank if needed. If you enter in two of these fields, the other will calculate automatically. For example, if you enter in a Start and a Finish date, the program will calculate the Duration. If you enter in a Start and a Duration, the program will calculate the Finish.

With Manual Scheduling, constraints, calendars, and relationships between activities are ignored. Instead, the activity is solely scheduled based on the date you set. Ideally, you should only use Manual Scheduling during the initial planning stage of the project. This is a way to do the same scheduling work you might have done on paper or in an Excel spreadsheet. As your project progresses, it is recommended to switch to the Automatic Scheduling mode. Most contracts will require projects to schedule using the Critical Path Method of scheduling. Manual Scheduling doesn’t do this, and won’t be sufficient past the initial planning stage.

What is Automatic Scheduling?

Automatic Scheduling doesn’t allow you to choose dates for the task. Instead, these dates are calculated based on data that you define. This is the method of scheduling that Microsoft Project was initially designed for. It is also the method of scheduling used in most other major scheduling applications, such as Primavera P6 and Oracle Primavera Cloud. Although it’s not the default method, you can switch to this scheduling mode at any time.

Automatically scheduled tasks calculate an ideal Start and Finish date for you. Unlike Manual Scheduling, you do not choose dates for your activities. Based on the duration of the activity and the relationships you’ve assigned, MS Project will determine the best dates for each activity. Automatic Scheduling makes use of the Critical Path Method, an algorithm that calculates activity dates to ensure the project completes on time. This method of scheduling will save you a lot of time and work. You won’t need to schedule every task one by one – instead, the program will map out these dates for you.

With Automatic Scheduling, all you need to do is set a Project Start date, add activities, and tie your activities together. The program will set your first task to start on the Project Start date. From there, it will follow the relationship ties to calculate when each subsequent task should start and finish. As you assign relationships, your activities will automatically move in the Gantt Chart, providing an ideal Start and Finish date.

With Automatic Scheduling, calendars and relationships will apply to activities. The calendar will determine when the activity will work and when it won’t. Relationships, on the other hand, will determine the order in which you should perform the activities. You can choose to have activities performed sequentially, or in parallel. 

Auto Scheduling and Constraints

Automatic Scheduling also allows you to use Constraints. Constraints let you to set a specific date for the activity to start or finish. This is important for work that’s outside of your control, such as if you have work site restrictions. With constraints, you can even choose whether you want the constraint to follow the logic assigned, or override it. Essentially, constraints allow you to choose dates for your activities to start and finish. However, these should not be overused. The majority of your activities should be driven by the relationships and logic you’ve assigned.

For most contracts, this method of scheduling is required. If your project contract says anything about using the Critical Path Method, make sure you’re utilizing Automatic Scheduling. 

Which Method of Scheduling Should I Use?

Although you can switch between the two modes of scheduling for each activity, you should stick to just one for the project. For almost all project schedules, we recommend using Automatic Scheduling. 

As mentioned above, most contracts will require your schedule to use the Critical Path Method – which Automatic Scheduling does.  Additionally, Automatic Scheduling is much easier. Instead of having to come up with a date for each activity, the program will calculate dates for you. Automatically scheduled projects tend to be more realistic, as the program will only allow an activity to start once its predecessor activities have finished. Manual scheduling, on the other hand, does not have this safe guard in place.

If you want to use Manual Scheduling, you should only do it during the initial planning stages of the project. Once you develop your activities further, you’ll want to switch the scheduling mode to Automatic. Your project schedules will typically be rejected if you use Manually scheduled activities.

Setting the Default Scheduling Mode

It’s recommended to set the Scheduling Mode to Automatic when first opening the program. You can adjust the default scheduling mode two ways: in the Status bar or in the Project Options window.

From the Status Bar, simply click within the New Tasks option. Here, you can change the default for new tasks going forward. However, this won’t adjust any activities you’ve already added. Therefore, you should make this adjustment before adding tasks to the project.

You can also adjust these settings in the Project Options window by selecting File > Options. Here, select the Schedule tab. Under Scheduling options for this project, you can switch the scheduling mode from Manual to Auto, or vice versa. Again, this will only affect activities added after making the adjustment – it won’t adjust any activities already added to the schedule.

Summary

Microsoft Project offers two methods of scheduling: Manual Scheduling and Automatic Scheduling. For new users, it may be difficult to know which of these to use. Manual Scheduling allows you to set a date for each activity – you’re choosing exactly when they start and finish. Although this is the default scheduling mode, it isn’t always the best option to use. The other option, Automatic Scheduling, lets the program come up with the task dates for you. Based on the task’s duration and relationships, Automatic scheduling will use the critical path method algorithm to determine when each activity should start and finish. Most project schedules will require you to use the Automatic Scheduling mode. Beyond this, automatic scheduling tends to be easier and more realistic as well. It’s recommended to switch the scheduling mode to Automatic whenever you open or create a new project in Microsoft Project.

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Lauren Hecker is a Microsoft Project, Primavera P6, and Oracle Primavera Cloud Instructor who 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!