What it means
A client may ask for a new feature, different material or earlier finish date. The request sounds small, but it can affect completed work, supplier orders, staffing and dependencies.
A change estimate makes those effects visible before the team commits to a price or deadline. Describe the change in a versioned request and assign an owner for the estimate, and if several options are possible, price each against the same baseline.
Include any work already authorised so the request does not accidentally charge twice for an existing obligation. Start with the existing baseline by asking what was already included and what work would no longer be needed.
Add direct materials and labour for the new request, then rework of work already done, design, permits, freight or testing where relevant. A change can save cost in one area while adding it elsewhere, so state whether figures include tax, contingency and overhead.
Assess time separately, since an added task may fit in spare capacity or move the critical path and delay completion. If acceleration is requested, overtime and expedited materials may cost more, but do not convert every extra day into a financial penalty without checking the contract and actual schedule effect.
Show uncertainty and options, since a rough early estimate may use ranges and provisional assumptions while a fixed quote requires more detailed scope. If information is missing, list it and set a date for a revised estimate rather than hiding uncertainty behind a precise number.
Approval should name the exact change, price basis and schedule impact together. State whether the estimate is a cost forecast for internal approval or a price offered to the customer, because margin, tax and contract terms can make the quoted price different from incremental cost.
Do not label a cost-saving alternative as a customer credit without checking the agreement. Keep the estimate linked to the change request and final decision, since a verbal "go ahead" can be disputed later if one party assumed a free tweak and the other assumed a billable variation.
After completion, compare actual cost to the estimate to improve future pricing. For managers, the estimate supports a choice to accept, defer, simplify or reject, and its value is in exposing trade-offs, not in making every requested change look affordable.
In practice
Real-world examples.
Example
A shop fit-out client changes floor material after installation has begun; the estimate includes new material and removal of work already completed.
Example
A software project drops one feature and adds another; the team credits avoided work and prices the additional design and testing.
Example
A video client asks for a different location after bookings are made; the producer includes cancellation charges and new travel costs.
Formula
Calculation
Incremental change cost = Added work + Rework + Change-specific delay or acceleration costs - Avoided original work
Worked example. A fictional project change adds AED 8,000 of material, AED 5,000 of labour and AED 2,000 of rework, while avoiding AED 3,000 of original work.
- Estimated incremental cost = AED 8,000 + AED 5,000 + AED 2,000 - AED 3,000 = AED 12,000.
- The quoted price may also include agreed margin and tax; cost is not automatically the selling price.
The numbers are illustrative, not a contractor quote.Case study
Seen in the real world.
This illustrative and entirely fictional example follows Oak Construction, an invented small fit-out firm. A client asked to move a partition after electrical work had begun. The site manager said it would be easy and started the change. Later, Oak sent an invoice including demolition, new cable routing and a delayed inspection.
The client thought only a drawing had been changed. Oak reconstructed the baseline and extra work, then negotiated the disputed amount. For later requests, it used a short change estimate with scope, cost range, schedule and assumptions, signed before work began except for genuine urgent safety changes. The process did not stop the client from making changes.
It let both parties choose them with a clearer view of cost and time. The next request involves two options for cabling. Oak compares material, labour, inspection and delay assumptions for each. It records which option the client selected and the date of approval, so a later invoice can be traced to a decision rather than a memory of the discussion.
Watch out
Common mistakes.
- Pricing only new materials while ignoring rework, testing, cancellation and schedule effects.
- Presenting a rough estimate as a fixed quote without stating assumptions and exclusions.
- Starting work on a material change before the authorised person reviews scope, price basis and timing.
Questions
People also ask.
Is an estimate the same as an approved change order?
No. The estimate informs the decision; the approved order records the agreed scope and terms.
Should avoided work be credited?
Yes, where the change genuinely removes work or cost, subject to commitments and contract terms.
What if the cost cannot be known yet?
Show a range, provisional amount or agreed method and identify what evidence will finalise it.
From the founder's library
Take it further with the book.
Build your financial confidence beyond this definition. Shihan's full-length guide, Accounting Fundamentals, takes the same plain-English approach and turns it into a complete, practical playbook for non-finance managers, business owners and students - with chapter-end quiz answers and presentation slides included.
25% off with code MMHQ25, applied at checkout. Priced in USD - checkout may show the equivalent in your local currency.
View the book and save 25%