To create a Microsoft Project baseline, open the approved schedule and select Project > Set Baseline > Set Baseline. Choose the unnumbered Baseline, select Entire Project, and then select OK. Project copies the current schedule values into protected comparison fields that remain available as the working schedule changes.
The menu steps are simple. However, a useful baseline requires more than selecting a command. First, confirm that the schedule represents the authorized scope, logic, calendars, durations, resources and costs. On a controlled program, also document the approval date and preserve the source schedule before changing baseline data.
What a Microsoft Project baseline records
A baseline is a saved set of planned values inside the project file. It does not create a separate schedule, freeze the current plan or prevent later updates. Instead, it gives Project a fixed reference for comparing the approved plan with current and actual performance.
According to Microsoft’s baseline guidance for Project desktop, a full baseline records reference data across five main categories:
- Start dates
- Finish dates
- Durations
- Work
- Costs
Project stores these values for tasks, resources and assignments where applicable. For example, the Baseline Start field contains the planned start at the time the baseline was saved. The Start field continues to show the current calculated start as the schedule changes.
The distinction matters. The baseline shows the approved target, while the current schedule shows the latest execution forecast. The GAO Schedule Assessment Guide describes the same management principle: programs compare the current schedule with the baseline to identify variance from the agreed plan.
Prepare the schedule before setting the baseline
Do not baseline an unfinished schedule simply because work is about to begin. The baseline will preserve existing defects along with the valid plan. Therefore, perform a focused schedule review first.
Confirm scope and schedule structure
Verify that the schedule includes the authorized work and required deliverables. The work breakdown structure should support clear ownership, reporting and integration with other program-control systems. If you are developing a defense program schedule, review how to structure an Integrated Master Schedule using the WBS.
Validate logic and dates
Check that detailed activities have appropriate predecessors and successors. Also review calendars, constraints, lags, leads, deadlines and external dependencies. Then trace the critical and near-critical paths to confirm that the calculated completion dates reflect the intended execution plan.
Baseline dates should result primarily from durations, calendars and network logic. Avoid forcing activities onto target dates with unnecessary hard constraints. Those constraints can conceal the schedule’s true forecast and reduce the value of later variance analysis.
Review durations, resources and costs
Confirm that remaining durations and work estimates are realistic. In addition, review resource assignments if the file supports resource planning or earned value calculations. Project captures baseline work and cost only from the information present when you save the baseline.
Microsoft explains that the Baseline Cost fields preserve the planned costs in the Cost fields when the baseline is saved. If the schedule lacks valid resource rates, work assignments or fixed costs, its baseline cost values will not represent an authoritative program budget.
Resolve status and approval questions
Ideally, establish the original baseline before routine progress updates begin. If the file already contains actual starts, actual finishes or completed work, determine whether you are creating an original baseline, reconstructing one or implementing an approved change.
For a formal Integrated Master Schedule (IMS), save a controlled copy of the reviewed file. Record the baseline date, approval authority, schedule version and any applicable change-control reference. These steps support baseline traceability when managers or customers later ask why dates changed.
How to set a Microsoft Project baseline
- Open the approved project file. Confirm that you are working in the correct schedule version.
- Select the Project tab. Locate the Schedule group on the ribbon.
- Select Set Baseline, then Set Baseline. Project opens the Set Baseline dialog box.
- Choose Baseline. Use the unnumbered Baseline for the primary approved plan unless your program’s documented procedure specifies another field set.
- Select Entire Project. This captures baseline values for the complete schedule.
- Select OK. Save the project file after Project writes the baseline values.
Microsoft Project can store 11 full baseline sets: Baseline plus Baseline1 through Baseline10. Numbered baselines can preserve approved revisions, planning snapshots or comparison points. However, define their purpose before using them. Otherwise, different analysts may interpret the same baseline fields differently.
Verify that the baseline was saved correctly
Never assume the baseline worked merely because Project displayed no error. Instead, inspect both the fields and the Gantt bars.
Review baseline fields
Add the following columns to a task view:
- Baseline Start
- Baseline Finish
- Baseline Duration
- Baseline Work, if resources are used
- Baseline Cost, if costs are used
- Start Variance
- Finish Variance
Baseline dates should now contain values for the baselined tasks. Immediately after baselining, the current and baseline dates should generally match unless the schedule changed during the process.
Use the Tracking Gantt
Select View > Gantt Chart > Tracking Gantt. Then apply the Variance table if you want a field-based comparison. Microsoft’s guidance on reviewing schedule progress explains that the Tracking Gantt displays current schedule bars alongside baseline bars.
As the project advances, the current bars move when forecasts change. The baseline bars remain in their saved positions. This visual comparison helps a scheduler identify slips, early starts and downstream effects before preparing a formal variance narrative.
Entire Project versus Selected Tasks
Use Entire Project when establishing the initial baseline. The Selected tasks option is mainly useful when adding approved work or implementing a controlled change that affects only part of the schedule.
Selected-task updates require care because Project can roll revised baseline values into summary tasks. The dialog box provides options to roll data to all affected summaries or from subtasks into selected summary tasks. A poor selection can produce summary baseline dates, work or costs that no longer reconcile with the underlying tasks.
Before updating selected tasks, identify every affected activity, milestone, summary task and assignment. Then compare the schedule before and after the change. On a controlled program, retain the authorization and include the update in the baseline change log.
Full baselines versus interim plans
Microsoft Project also provides an interim plan option. An interim plan normally copies start and finish values into custom Start and Finish field pairs. It does not capture the same range of duration, work and cost data as a full baseline.
Therefore, use a full numbered baseline when you need a comprehensive comparison point. An interim plan may help with limited date snapshots, but it is not a substitute for an approved schedule baseline or a Performance Measurement Baseline (PMB).
The Microsoft instructions for baselines and interim plans also allow baseline data to be copied between baseline field sets. If you use that capability, document the source, destination, purpose and copy date. Otherwise, the file may retain values without enough history to explain them.
Example: baselining a fictional defense program schedule
Assume the fictional Harbor Shield Radar Upgrade has completed its planning review. The IMS contains 1,850 activities covering design, hardware procurement, software development, integration, test and deployment. The program team has reviewed the critical path, resource assumptions and contract milestones.
The scheduler archives the approved file and saves the plan in the unnumbered Baseline fields. Three months later, the customer authorizes an additional cybersecurity test event. The program processes the change through its approved change-control procedure.
Instead of overwriting the original baseline without a record, the scheduler preserves the original values and saves the authorized revised plan in Baseline1. The schedule basis document and change log identify Baseline as the original plan and Baseline1 as the approved post-change plan.
Management can now compare the current forecast with either reference point. The team can also distinguish execution variance from the effect of the authorized scope change. This distinction is central to understanding replanning versus rebaselining.
Microsoft Project baselines and EVMS
Selecting Set Baseline in Microsoft Project does not, by itself, establish an approved PMB. In an Earned Value Management System (EVMS), the PMB integrates authorized scope, schedule and time-phased budget. The scheduling tool is only one part of that control environment.
When EVMS is contractually required, applicable contract terms, agency procedures and the contractor’s approved system description govern baseline establishment and change control. For example, Federal Acquisition Regulation 34.202 addresses Integrated Baseline Reviews when EVMS is required. It focuses on the realism and integration of technical, schedule, resource and budget plans; it does not prescribe a Microsoft Project menu procedure.
Before using Project baseline cost or earned value fields for formal reporting, confirm that schedule activities align with the authorized budget and the cost system. For a broader explanation of that integration, see how the IMS supports earned value management and the guide to the Performance Measurement Baseline.
Common baseline mistakes
- Baselining before the schedule is ready. Missing logic, invalid dates and incomplete scope become part of the comparison point.
- Baselining only selected tasks by accident. Unbaselined tasks then show blank or zero baseline values.
- Overwriting the original baseline during routine status. This erases the evidence needed to measure variance against the approved plan.
- Using a new baseline to hide poor performance. Forecast movement alone does not justify rebaselining.
- Failing to define numbered baselines. Baseline1 and Baseline2 have little value if users do not know what each set represents.
- Confusing baseline dates with current dates. Baseline fields hold the saved target; Start and Finish fields show the current schedule.
- Ignoring summary-task rollup behavior. Partial updates can create inconsistent baseline values at higher WBS levels.
- Treating the software command as approval. Project stores data, but the program’s authorized process establishes and controls the official baseline.
Practical baseline control checklist
- Complete the schedule quality and logic review.
- Confirm authorized scope, milestones, calendars and assumptions.
- Verify resource and cost data if the schedule uses them.
- Archive the approved pre-baseline file.
- Set the baseline for the entire project.
- Inspect baseline fields and Tracking Gantt bars.
- Record the baseline date, version and approval reference.
- Define the purpose of every numbered baseline.
- Protect baseline changes through the applicable change-control process.
- Continue updating the current schedule without rewriting historical performance.
Once the baseline is established, status the current schedule using actual performance and realistic remaining forecasts. A disciplined process preserves the approved target while keeping the execution schedule current. The result is a Microsoft Project file that supports meaningful variance analysis, management decisions and customer reporting.