Primavera P6 Schedule Review: The Complete Checklist for Reviewing Contractor Schedules

You’ve downloaded the contractor’s XER file, opened it in Oracle Primavera P6, and you’re staring at 1,200 activities. Where do you start? What do you check? How do you know whether the schedule is logic-driven or date-driven?

Most P6 training teaches you how to build a schedule. Nobody teaches you how to review one you’ve received. That’s a problem, because the person reviewing the schedule is usually not the person who created it. You’re the employer’s representative, the project controller, or the client-side PM, and you need to decide whether this programme is fit for approval.

This guide provides a complete, step-by-step checklist for reviewing a contractor’s schedule submission in P6. It covers every check from opening the XER file through to generating your review report. For the tool-agnostic version of this discipline (the checks that apply whether you work in P6, MS Project, or a standalone analyser), see our baseline schedule review guide; this article focuses on carrying that discipline out inside Primavera P6. If you need broader context on schedule analysis principles, see our guide to construction schedule analysis.

The stakes are set by what good looks like. The Guggenheim Bilbao came in on time and 3 per cent under budget, one of the roughly 0.5 per cent of big projects that deliver on all their promises (Flyvbjerg and Gardner, How Big Things Get Done), because the hard thinking was done before construction started. A contractor’s programme is where you find out whether that thinking has been done on your project, and a structured review is how you check it before you approve the dates rather than after they slip.

What the SCL Protocol flags: The SCL Protocol identifies the same failure patterns a structured review looks for. Its paragraphs 1.45 to 1.47 call for complete logic (open ends create phantom float), warn against manually applied constraints that override the network, and caution against excessive leads and lags that hide work which should sit as visible, logic-linked activities.

What it means: Without a systematic review process, you’re approving a programme you can’t rely on for delay analysis, progress tracking, or dispute resolution. A structured P6 review takes 2-4 hours. Fixing the problems after approval takes months.

How to Open and Set Up a Contractor’s XER File in P6

Before you can review anything, you need to get the contractor’s submission into P6 and set up for efficient review.

Import the XER file

1. In P6, go to File > Import and select the XER file from the contractor
2. Choose the project(s) to import. If the submission contains multiple projects, import only the one you’re reviewing
3. After import, open the project and set it as the focused project
4. Verify the data date shown in P6 matches the data date in the submission letter

First check before you start: Does the project name, ID, and description match the contract? If the contractor’s internal project naming convention doesn’t align with the contract reference, note it. You’ll need to reconcile this when comparing against the baseline.

Create a review layout

Set up a dedicated review layout before you start checking activities. A well-structured layout saves time across every review step.

To create this layout: View > Columns and add the columns above. Save it as “Schedule Review” via View > Layout > Save As. You can reuse this layout across projects.

Set up review filters

Create these filters before you begin:

• Open Ends: Activities with no predecessor OR no successor
• Critical Only: Activities where Critical = Yes
• Constrained: Activities with a primary constraint assigned
• High Duration: Activities where Original Duration > 20
• Milestones: Activity type = Start Milestone or Finish Milestone

To create a filter: View > Filter > New and set the criteria. Save each filter with a descriptive name.

The P6 Schedule Review Checklist

The following 12 steps form a complete review of any contractor schedule submission. Work through them in order.

Step 1: Verify project information and settings

Open Project > Project Details and check:

• Project name and ID match the contract
• Data date is correct and current (this is the “as at” date for the schedule)
• Must-finish-by date matches the contractual completion date
• Calendar assignment at project level is appropriate
• Planned start date aligns with contract commencement

If the data date is wrong, every duration, float, and progress calculation in the schedule is wrong. This is your first gate: don’t proceed until the data date is verified.

Step 2: Check the work breakdown structure (WBS)

Switch to Project > WBS view and verify:

• The WBS reflects the complete contractual scope
• WBS levels are logically structured (typically 3-5 levels for a major project)
• Work packages are appropriately detailed
• No WBS elements exist without activities (empty nodes)
• No activities exist outside the WBS structure

A well-structured WBS makes the rest of the review faster. If the WBS doesn’t align with the contract scope, you’ll struggle to verify whether all required work is included later.

Step 3: Review activity details

Switch to the Activities view, Group and Sort by WBS, and scan:

• All contractual scope items represented as activities
• Activity IDs follow a consistent coding scheme (e.g. area-trade-sequence)
• Activity names are descriptive and unambiguous
• No duplicated or phantom activities
• Activity count is reasonable for project size (typically 500-2,000 activities for a major project)

Practical tip: A schedule with fewer than 200 activities for a $50M+ project is probably too coarse. A schedule with more than 5,000 activities is probably too detailed to manage. Both extremes create review problems.

Step 4: Check calendars

Go to Enterprise > Calendars and verify:

• Appropriate calendars assigned (5-day, 6-day, 7-day, weather, shutdown)
• Holiday and shutdown periods reflected in calendar definitions
• Calendar assignments consistent with work type (don’t assign a 7-day calendar to an administrative activity)
• No unnecessary custom calendars (more than 10-15 calendars for a single project is a warning sign)

Calendar issues affect float calculations, duration display, and critical-path determination. Two activities with identical logic can show different float values if they’re on different calendars.

Step 5: Review logic and dependencies

This is the most important step in the review. The entire credibility of the schedule depends on whether the logic is correct.

Apply your Open Ends filter. Check:

• No activities without predecessors (except the project start milestone)
• No activities without successors (except the project finish milestone)
• All activities connected to the network through logic links

Then review logic types:

• Relationship types are appropriate (the DCMA 14-Point Assessment targets 90% or more finish-to-start relationships)
• No circular logic (P6 will warn you during scheduling)
• No redundant dependencies
• Lags used appropriately: not hiding work that should be visible activities

The SCL Protocol, paragraph 1.45, states that “the Contractor’s proposed programme (and any revisions) should be prepared with sufficient detail using logic links (i.e. each activity is linked to both a predecessor and successor activity or milestone) to provide proper forward visibility so that the effect of delay and disruption events can be predicted with as much accuracy as possible.” Every open end violates this principle.

For detailed guidance on catching logic changes between updates, see our article on schedule manipulation detection.

Step 6: Validate the critical path

Apply your Critical Only filter and review:

• The critical path is clearly identifiable and contiguous
• Critical path activities match construction logic and contract milestones
• The longest path drives the project completion date
• Near-critical paths are reviewed (activities with less than 5 working days of float)
• No artificial float from constraints or hidden logic ties

To check whether the critical path is logic-driven: go to Tools > Schedule > Options and verify that “Define critical activities as” is set to “Total Float <= 0”. If the contractor has changed this to a different float threshold, note it and question why.

For a deeper understanding of how the critical path should be constructed and validated, see our guide to the critical path method in construction.

Step 7: Check float distribution

Add the Total Float column and sort by float value:

• Total float values are reasonable for the project stage
• No high-float activities hiding scope (the DCMA 14-Point flags float greater than 44 working days)
• No negative float on a baseline schedule (negative float means the schedule can’t meet the contractual date)
• Float ownership per contract is documented

A schedule where every activity has 50+ working days of float isn’t truly constrained; the logic isn’t driving the dates. A schedule with zero float on everything has probably been constrained to create that result.

For detailed float analysis, see our guide to total float vs free float.

Step 8: Review constraints

Apply your Constrained filter and check:

• Constraints used sparingly and justified in the programme narrative
• No excessive “must finish by” (MFO) or “must start on” (MSO) constraints overriding logic
• Only contractually required milestones constrained
• Soft constraints (SNET, FNET) used where flexibility is needed

The DCMA 14-Point Assessment, Check 5 (Hard Constraints), targets 5% or fewer activities with hard constraints. The SCL Protocol, paragraph 1.47, states that “manually applied constraints such as ‘must start’ or ‘must finish’ fixed dates, ‘zero float’ and other programming techniques that can have the effect of inhibiting a programme from reacting dynamically to change should be avoided.”

Hard constraints are the most common tool for manipulating a schedule’s appearance. If you find more than a handful, request justification for each one. For DCMA threshold context, see our guide to the DCMA 14-Point Assessment.

Step 9: Check activity durations

Apply your High Duration filter and check:

• Durations realistic and industry-appropriate
• No excessively long activities (the SCL Protocol, paragraph 1.46, suggests that “no activity or lag (other than a summary activity) should exceed 28 days in duration”)
• No unreasonably short activities (activities shorter than one day should be questioned)
• Durations consistent with resource assignments where loaded

The DCMA 14-Point Assessment, Check 8 (High Duration), flags activities longer than 44 working days. Construction practice is typically tighter: 20 working days is a common contractual maximum. The SCL Protocol’s recommendation of 28 days falls between the two.

Step 10: Verify milestone compliance

Apply your Milestones filter and verify:

• All contractual milestones present and dated correctly
• Milestone sequence matches contract requirements
• Interim completion dates achievable based on preceding logic
• No milestones missing from the schedule

Missing milestones are a red flag. If the contract specifies sectional completion dates and they’re not in the programme, the contractor can’t demonstrate compliance, and you can’t enforce it.

Step 11: Review resources and cost loading

Not all contracts require resource or cost loading. If yours does:

• Resources logically assigned to activities
• No over-allocation without levelling
• Cost-loaded where required by contract
• Earned value baseline established
• Resource curves appropriate

Go to Activities > Resource Assignments and scan for activities with zero budget or missing resource assignments. If the schedule is contractually required to be resource-loaded, every activity should have resources assigned. Unresourced activities in a resource-loaded schedule are incomplete.

Step 12: Run the schedule log and DCMA 14-Point

This is your final gate check before writing up your review.

To generate the schedule log:

1. Go to Tools > Schedule
2. Ensure “Log to file” is checked
3. Click Schedule
4. Click View Log to open the scheduling log

Key items in the schedule log:

To run the DCMA 14-Point macro in P6:

If your organisation has the DCMA macro installed:

1. Go to Tools > Schedule and run the DCMA macro
2. Review each of the 14 checks against the published thresholds
3. Flag any failing metrics for the contractor to address

If the macro isn’t installed, you can replicate the key checks manually using your filters and columns. The five checks most relevant to schedule review:

1. Check 1 (Logic): Filter for open ends; target 5% or fewer
2. Check 3 (Lags): Count relationships with positive lag; target 5% or fewer
3. Check 5 (Hard Constraints): Filter for MSO/MFO constraints; target 5% or fewer
4. Check 7 (Negative Float): Sort by total float; target zero
5. Check 8 (High Duration): Filter for activities > 44 working days; target 5% or fewer

For detailed DCMA metric definitions and thresholds, see our guide to the DCMA 14-Point Assessment.

Compare schedule updates in P6

When you’re reviewing a monthly update (not the initial baseline), schedule comparison is your most powerful tool.

To compare schedules in P6:

1. Go to Tools > Schedule Comparison
2. Select the baseline project and the current update project
3. Choose the comparison options: added activities, deleted activities, logic changes, duration changes, calendar changes
4. Run the comparison and review the results

What to look for:

Key insight: Unexplained logic changes between updates are the single strongest indicator of schedule manipulation. Every logic change should be explained in the programme narrative. If it isn’t, flag it.

For detailed comparison methodology, see our guide to baseline vs current schedule comparison. For help with XER files specifically, see our guide to XER file analysis.

Create a P6 layout optimised for schedule review

Beyond the review checklist columns (table above), add these columns for update reviews:

Recommended grouping and sorting

• Group by WBS: Review scope coverage and sequencing within work packages
• Group by Critical Path: Quickly identify all critical and near-critical activities
• Sort by Total Float ascending: See the most constrained activities first
• Sort by Variance Finish descending: Find the activities running furthest behind baseline

Save layouts

After setting up your review layout: View > Layout > Save As and name it descriptively (e.g. “Baseline Review” or “Monthly Update Review”). Export the layout via View > Layout > Export so other team members can use the same configuration.

Generate a schedule review report in P6

After completing the review, document your findings.

Key reports to generate

Export for project team communication

• Export to PDF: File > Export > PDF. Use for formal review correspondence.
• Export to Excel: Select activities, Edit > Copy, paste into Excel. Use for detailed analysis and annotation.
• Export to XER: File > Export > XER. Use if the contractor needs to reimport your annotated version.

Create a structured review memo

Your review memo or letter to the contractor should follow this structure:

1. Submission reference: Date received, project name, data date of schedule
2. Overall assessment: Pass/fail with qualifications
3. Findings by step: Reference each checklist step, note pass or issues found
4. Required corrections: Specific activities, logic ties, or constraints that must be fixed
5. Recommended improvements: Issues that don’t fail a threshold but are below best practice
6. Deadline for resubmission: Per contractual requirements

Common P6 Schedule Issues and How to Flag Them

For detailed guidance on identifying deliberate manipulation of these issues, see our article on schedule manipulation detection.

P6 vs Dedicated Analysis Tools for Schedule Review

P6 is the industry-standard scheduling tool, but it has limitations for schedule review.

P6 is indispensable for creating and maintaining schedules. For review, it provides the raw data and most of the checks you need. But if you’re reviewing multiple schedule submissions regularly, or you need to produce review reports without a P6 license, a dedicated analysis tool like ScheduleLens can save hours per review.

For a broader comparison of the leading schedule analysis tools, see our dedicated guide.

Quick-Reference: P6 Navigation for Each Check

Key Takeaways

• Most P6 content teaches schedule creation. This guide covers schedule review: what to check when you’ve received someone else’s schedule and need to approve it.
• Set up a dedicated review layout and filters before you start. The 10-column layout and five filters in this guide cover every major check.
• Work the 12-step checklist in order: project information, WBS, activities, calendars, logic, critical path, float, constraints, durations, milestones, resources, DCMA 14-Point.
• Logic review (Step 5) is the most important step. If the logic is wrong, the entire schedule is unreliable. Every open end violates the SCL Protocol’s requirement for proper forward visibility.
• Schedule comparison is your most powerful tool for update reviews. Flag every unexplained logic change.
• The DCMA 14-Point Assessment is a minimum standard, not a target. A schedule can pass all 14 checks and still have quality issues.
• Document your findings in a structured review memo. Don’t just flag problems; specify the corrections required and the deadline for resubmission.