Contractor document guide · Side-by-side
One assigns the work. One changes the deal.
A work order usually sends authorized work into the field. A change order modifies what the parties previously agreed. Many jobs need both, in that order.
The short answer
Classify the document by effect, not title.
A work order typically answers: who goes where, when, to do which already-approved task, under what site and pricing rules, and what must be recorded at closeout.
A change order answers: what in the original agreement is being added, deleted, or replaced, and how does that affect price, payment, time, risk, and authorization? Organizations use names differently, so read the governing agreement and actual content.
Comparison matrix
Different triggers, different authority.
Work order: execute
Starts, assigns, schedules, tracks, or closes approved work.
Change order: modify
Amends agreed scope, price, payment, time, or another term.
Work order: ready work
Approved estimate, recurring service, contract task, repair request, or planned visit.
Change order: changed deal
Customer request, discovery, design/inspection revision, quantity, deletion, substitution, or delay effect.
Work order: under authority
References the contract, estimate, approval, master agreement, or standing service terms.
Change order: changes authority
Becomes part of or modifies the original agreement through its change process.
Work order: applies pricing
Uses approved fixed, unit, T&M, diagnostic, or NTE rules and tracks actuals.
Change order: revises pricing
Adds and subtracts work, credits, adjustments, revised total, payment, and potentially time.
Work order: role-dependent
Dispatcher, lead, technician, and customer acknowledgement vary by workflow.
Change order: modification authority
Requires the parties or representatives authorized under agreement and law to approve the amendment.
Work order: field result
Labor, parts, tests, evidence, status, exceptions, follow-up, and completion acknowledgement.
Change order: approved baseline
Executed amendment and attachments retained with the controlling contract and reflected in downstream records.
Lifecycle
Use the change order before the revised work order.
- 01
Agreement or estimate is approved
The customer and contractor establish the original scope, price, schedule, and governing terms.
- 02
Work order dispatches the task
The field receives site, scope, assignment, access, pricing, safety, materials, and closeout requirements.
- 03
A changed condition or request appears
The field documents the trigger and stops at the authorization boundary.
- 04
Change order amends the agreement
Authorized parties approve changed scope, additions/credits, payment, schedule, exclusions, and evidence.
- 05
Revised work order returns it to the field
The newly approved work becomes an executable assignment with current attachments and limits.
- 06
Closeout records actual performance
The field documents what was completed under both the original and changed authority.
Which document?
Five common field decisions.
Dispatch an approved faucet replacement
Scope and fixed price are already accepted. Assign technician, access window, specified faucet, protection, test, and closeout evidence.
Customer upgrades the faucet after ordering
Replace the product decision, address return/restocking, changed price, lead time, payment, and signature before new order.
Rot is discovered behind planned siding repair
Change order approves framing/sheathing repair and effects; revised work order gives crew the new boundary, materials, safety, and evidence.
Perform recurring quarterly maintenance
The service agreement already defines tasks and rates. Each visit is scheduled, assigned, and closed through a work order.
Owner deletes one room from a painting contract
Amend deleted scope, committed cost, credit, revised total, payment, and schedule. Then update crew work orders.
Four-question selector
Choose by what the record does.
Does it alter agreed scope?
If yes, use the required change or amendment process.
Does it change money or time?
If yes, update price, payment, schedule, and authority, not just field notes.
Is the work already authorized?
If yes, a work order may assign and track execution under that authority.
Will the field need a new assignment?
After approval, issue or revise the work order so execution matches the amended agreement.
Signature meaning
Do not reuse one signature label.
The signature block should state what the signer is doing. A customer acknowledgement at closeout is not automatically approval of added scope.
- Work-order issuance
- [Dispatcher/manager assigns the described authorized work to the named field person]
- Field acknowledgement
- [Technician/crew lead confirms receipt and review of assignment, site information, and known controls]
- Customer work authorization
- [Authorized customer approves only the stated work and pricing under identified governing terms]
- Customer completion acknowledgement
- [Confirms stated site facts, demonstration, or completion; define whether it authorizes billing]
- Change-order approval
- [Authorized party agrees to amend identified scope, price, payment, schedule, and attachments]
Document labels do not override the agreement or law. Define the signer's capacity, authority, intent, and the exact version signed.
Research basis
The clean distinction is execution versus modification.
FAR Part 43 expressly excludes orders for supplies or services that do not otherwise change contract terms from its contract-modification rules, while FAR 43.2 treats change orders as written contract changes within authorized areas. That federal system is not a residential rule, but it illustrates the conceptual boundary.
Oregon procurement guidance says change orders can alter tasks, standards, methods, price, or schedule and must follow the original contract’s change provisions. GSA facilities guidance treats work orders as operational records carrying description, resolution, timestamps, notes, labor, costs, closeout, and barriers. California and Oregon residential guidance reinforce that changed contract scope should follow the applicable written change process.
- FAR Part 43: orders versus contract modifications ↗
- Oregon Procurement Manual: change orders ↗
- GSA: operational work-order records ↗
- California CSLB: written contract changes ↗
Public procurement terminology is illustrative, not controlling for private construction. Follow the actual agreement, organization procedure, and applicable law.
Change order vs. work order questions
Can a work order change the contract?
A document may have contractual effect based on its content and governing terms, but ordinary dispatch should not bypass the required amendment process.
Do both documents need customer signatures?
Not always. Change approval requires authorized agreement modification; work-order issuance may be internal. State the purpose and signer authority.
Can the same software record serve both functions?
Possibly, if it clearly separates the document type, authority, content, version, signatures, and workflow required for each function.
What happens after a change order is signed?
Retain it with the contract, update price/payment/schedule records, and issue a current field assignment or revised work order.
Right record, right moment
Approve the change, then dispatch the work.
Use JobSign for customer-facing scope changes and clear work authorizations before the field moves.
Get JobSign →