Basis of Estimates Worksheet
A handbook-style basis of estimates worksheet with field guidance, workflow, review checks and source-derived example evidence.
What this artefact controls
Basis of Estimates Worksheet should be treated as a decision instrument, not as paperwork completed for its own sake. Its practical value comes from making the underlying decision, evidence, ownership and review cycle visible. In this handbook, the supplied source structure is retained as the factual basis while the surrounding guidance explains how to complete, review and maintain it in day-to-day project delivery.
The source set repeatedly links project documents to broader control relationships: scope creates the work to be scheduled and costed; resources execute that work; stakeholders influence acceptance and change; risk captures uncertainty; quality establishes evidence of conformance; and performance information explains whether the project is still moving toward its intended outcome. Basis of Estimates Worksheet belongs in that integrated system. It should therefore use identifiers and terminology consistent with adjacent project records so that a reviewer can trace a decision across documents without relying on memory.
Before filling any field, write one sentence describing the decision or control action the completed artefact must support. Then identify the accountable owner, contributors, reviewers, approval authority and next review trigger. This prevents a common failure in project documentation: every box is filled, but nobody can explain what decision the document enables or who must act when conditions change.
How the information fits together
This visual is an HTML/CSS interpretation for the KEVOS article reader. It conveys the decision structure without embedding the supplied source artwork as a screenshot.
Complete the template with traceable information
The following field map is extracted from the supplied blank or completed source document where text was available. Wording has been normalised for web readability, but the source structure remains the basis. Where a field is not applicable, record why rather than silently leaving a potentially important control blank.
| Source field / section | What to record | Review test |
|---|---|---|
| Parametric Estimates | State the condition in testable terms and identify the evidence or method that proves it has been satisfied. | A separate reviewer can verify it objectively. |
| ID | Assign a unique, stable identifier that can be referenced from reports, changes, risks, requirements or evidence. | The entry is specific, traceable and reviewable. |
| Cost Variable | Record currency, price date, inclusion boundary and source of the value; separate estimate, baseline, actual and forecast. | Units, currency and basis reconcile. |
| Cost per Unit | Record currency, price date, inclusion boundary and source of the value; separate estimate, baseline, actual and forecast. | Units, currency and basis reconcile. |
| Number of Units | Record the minimum evidence needed for number of units to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Cost Estimate | Record currency, price date, inclusion boundary and source of the value; separate estimate, baseline, actual and forecast. | Units, currency and basis reconcile. |
| Analogous Estimates | Record the minimum evidence needed for analogous estimates to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Previous Activity | Use the identifier from the approved scope or schedule model so the record can be traced to the work it controls. | The entry is specific, traceable and reviewable. |
| Previous Cost | Record currency, price date, inclusion boundary and source of the value; separate estimate, baseline, actual and forecast. | Units, currency and basis reconcile. |
| Current Activity | Use the identifier from the approved scope or schedule model so the record can be traced to the work it controls. | The entry is specific, traceable and reviewable. |
| Multiplier | Record the minimum evidence needed for multiplier to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Three-Point (PERT) Estimates | Record the minimum evidence needed for three-point (pert) estimates to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Optimistic | Record the minimum evidence needed for optimistic to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Most Likely | Record the minimum evidence needed for most likely to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Pessimistic | Record the minimum evidence needed for pessimistic to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Equation | Record the minimum evidence needed for equation to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
| Expected Cost | Record currency, price date, inclusion boundary and source of the value; separate estimate, baseline, actual and forecast. | Units, currency and basis reconcile. |
| Labor | Record the minimum evidence needed for labor to support the create a defensible cost and funding model that can be approved, monitored and forecast throughout delivery. | The entry is specific, traceable and reviewable. |
Blank web-ready structure
This compact version is designed for copying into a project working note or for translating into your organisation’s controlled form. It is not a claim that these are the only fields required by every organisation, contract or jurisdiction.
What the uploaded example demonstrates
The source set uses a recurring worked project — Mary’s Consulting and its new company website — to show how project artefacts connect. The examples are useful because the same scope, team, costs, risks, stakeholders and milestones recur across multiple forms, allowing the reader to see how one project decision propagates through the documentation system. Any numerical value below is a source example or a calculation explicitly identified as such; it should not be treated as a universal project standard.
- Documents the estimating techniques used to derive activity cost estimates: parametric, analogous, and three-point. Bottom-up estimates are on the next page.
- PERT (beta) weighting: tE = (O + 4M + P) / 6. Used for activities with significant uncertainty.
- Bottom-up estimate decomposes selected work packages into cost components: labor, material, supplies, equipment, travel, other direct costs (ODC), indirect costs, and reserve.
- Project Date May 14,
- Title: Prepared: 2026
- A006 PM hours interviewing $65/hr 30 hours $1,950
- A014 Writer hours per page $50/hr 100 hours (~25 pages × 4 hrs) $5,000
- A015 Writer hours per case study $50/hr 80 hours (20 cases × 4 hrs) $4,000
Step-by-step workflow
For controlled project records, the final step is not “save the file”. The final step is to make the current approved state discoverable, communicate the decision to affected people and define the next review trigger. That trigger may be a phase gate, threshold breach, approved change, new stakeholder, supplier event, forecast movement, risk trigger or a scheduled review date.
Review checklist before approval or use
- Estimate units and currencies are explicit.
- The source and date of rates are recorded.
- Contingency is not confused with management reserve.
- The total reconciles from activity level to project level.
- Funding timing matches the schedule and contractual payment profile.
- Forecast logic explains significant variance rather than only reporting it.
Run the review from the perspective of a competent person who did not attend the drafting meeting. If they cannot reconstruct the basis, current state and required next action from the record and its cited evidence, the artefact is not yet controlled enough for a material decision.
Common mistakes and recovery actions
Presenting a single cost number without a basis.
Recovery: return to the approved objective or baseline, identify the missing evidence or decision owner, and record the corrective action before proceeding.
Mixing estimates from different currencies or price dates.
Recovery: return to the approved objective or baseline, identify the missing evidence or decision owner, and record the corrective action before proceeding.
Double-counting contingency.
Recovery: return to the approved objective or baseline, identify the missing evidence or decision owner, and record the corrective action before proceeding.
Ignoring committed costs that are not yet invoiced.
Recovery: return to the approved objective or baseline, identify the missing evidence or decision owner, and record the corrective action before proceeding.
Treating a favourable early cash position as evidence that the project is under budget.
Recovery: return to the approved objective or baseline, identify the missing evidence or decision owner, and record the corrective action before proceeding.
Keep the document alive after first approval
A project artefact is only useful while its status is known. Give it a unique identifier, version, owner, approval state and effective date. Define what types of change require reapproval and what updates can be made administratively. Retain superseded versions when the record is needed to explain a historical decision, claim, audit, acceptance or lesson.
Use the document in reviews by focusing on exceptions and decisions rather than reading every field aloud. Ask what has changed since the last review, what assumption has been invalidated, what threshold has been crossed, which decision is now due and which action remains without an owner. This converts the artefact from static documentation into a control mechanism.
At hand-off, confirm that downstream users can interpret the identifiers, units, assumptions and status values without relying on the original author. For project close-out, make sure unresolved items have an operational owner and a clear retention location. A closed project should not leave behind orphaned risks, undocumented support obligations, unverified benefits or ambiguous acceptance evidence.
Source basis and limitations
This page is an original KEVOS handbook synthesis grounded in the uploaded source files. It intentionally paraphrases and restructures the material for practical application rather than reproducing the source documents as images. Where the source contains an illustrative project value, that value remains an example. Where a required blank source was absent, the limitation is stated explicitly rather than silently inventing a missing form.
- PMBOK+8+Plans+and+Documents/Estimate Costs/Basis_of_Estimates_BLANK.pdf
- PMBOK+8+Plans+and+Documents/Estimate Costs/Basis_of_Estimates_FILLED.pdf
Current authoritative context used for the reference pages: Project Management Institute, PMBOK® Guide — Eighth Edition and the 2026 PMP Examination Content Outline. The article package does not reproduce substantial PMI publication text.