forProject Technology

Basis of Estimate

Basis of Estimate (BOE)

EVM Terms Reviewed by forProject Technology - updated Sep 2026
Quick definition: A Basis of Estimate (BOE) is the documented rationale behind a cost or resource estimate for a specific piece of project scope.

A BOE explains how an estimate was derived, whether developed initially or as part of a later re-plan. It can apply to a WBS Element, Control Account, Work Package, Planning Package, or Summary Level Planning Package. It typically captures the assumptions, methods, and data used to arrive at the number.

Why it matters

Without a documented BOE, an estimate is just a number with no way to judge whether it's reasonable or to update it intelligently when circumstances change. A clear BOE also supports audits and reviews by showing exactly how budget figures were derived.

Also known as
BOE
Used in
Control Account Plan development; re-planning

FAQ

Is a BOE only created at the start of a project?
No — a BOE is also developed whenever a subsequent re-plan produces a new estimate.
What level of the WBS needs a BOE?
A BOE can apply at several levels — WBS Element, Control Account, Work Package, Planning Package, or Summary Level Planning Package.
Definition maintained by forProject Technology.
© 2026 forProject Technology, Inc.
forProject