Variation Order vs Change Order: Is There a Difference Under FIDIC?
A project manager used to US-influenced contracts joins a FIDIC job and asks the Engineer for a "change order" on an instructed rerouting of ductwork. The Engineer's team looks blank — on this contract, the word is "Variation." Same instruction, same money, same time, but only one of the two words actually does anything under the contract. This guide clears up what's the same, what's different, and why the label matters more than it sounds like it should.
What FIDIC Actually Calls It: the Variation
Under Sub-Clause 13.1 of the FIDIC 1999 Red Book, a Variation is any change to the Works instructed by the Engineer — adding work, omitting work, or changing how, when, or in what sequence the work is carried out. It is a defined contract term with a defined procedure attached to it.
Once instructed, a Variation runs on its own track. The Contract Price is adjusted under Clause 12, using Bill of Quantities rates where they fit and fair new rates where they do not, and the Time for Completion is adjusted where the change genuinely affects the programme. Reasonable profit is ordinarily part of that valuation, and the Contractor does not have to prove fault or loss — the entitlement comes from being instructed.
"Variation" is the only word for this that appears in the FIDIC Conditions of Contract, in both the 1999 and 2017 editions. Nowhere in either suite does the phrase "change order" appear as a defined term.
Key Takeaway: Under FIDIC, the only defined word for an instructed change is Variation, under Sub-Clause 13.1 — with its own Clause 12 valuation route, including time and normally reasonable profit.
Where "Change Order" Comes From
"Change order" is not a FIDIC concept — it is the everyday term on contracts built around North American forms, such as the AIA A201 family, where it is a specific, signed document that authorises and prices a change.
The term travels with people, not with contracts. A project director used to US-administered jobs, or simply an old habit, can bring "change order" onto a FIDIC site even though the governing contract has never heard of it. Once it is in the room, it gets used loosely — in meeting minutes, emails, site instructions — without anyone checking whether it lines up with what the contract requires.
That is where the risk starts. Not the words themselves — "change order" simply carries no obligations on a FIDIC contract by itself. It is a label, not a mechanism.
Key Takeaway: "Change order" comes from North American standard forms, not FIDIC. It reaches a FIDIC project through habit, not contract wording, and on its own triggers nothing under the FIDIC procedure.
Same Event, Different Contractual Weight
In most cases, a "change order" and a "Variation" describe exactly the same real-world event: the Engineer or Employer's side asks for something different than what was originally scoped, and the Contractor carries it out. The confusion is not usually about what happened — it is about what the label does for the Contractor afterward.
A genuine Variation, correctly identified as one, gives the Contractor a defined route: Clause 12 valuation, a time adjustment where warranted, and a paper trail the contract recognises. A "change order" never connected back to Sub-Clause 13.1 in writing gives none of that automatically — it might get valued informally or disputed later, precisely because nobody tied it to a clause when it happened.
So the practical answer is: usually the same thing, but only one name opens a door in the contract. "Change order" is fine as shorthand between colleagues — it becomes a problem only when it is the only label the instruction ever gets.
Key Takeaway: The underlying event is usually identical. The risk is that "change order" alone gives the Contractor no defined contractual route — only naming it a Variation under Sub-Clause 13.1 does that.
The Practical Risk of Leaving It at "Change Order"
Two problems show up repeatedly when a project relies on change order language without formalising the FIDIC side of it.
- The clock gets missed. Where a separate Sub-Clause 20.1 notice is needed for consequential delay, the clock runs from the instruction date. If the instruction was only logged as an internal "change order," nobody may have flagged that date, and the clock can run out unnoticed.
- The valuation gets argued over from scratch. Without a written link back to Sub-Clause 13.1, the Engineer can treat a "change order" as an informal courtesy rather than a binding instruction, leaving the Contractor to argue entitlement after the fact.
Neither problem is caused by using the wrong word — both come from never converting the informal label into the contractual one while there is still time.
Key Takeaway: The risk is not the vocabulary — it's leaving an instruction as an informal "change order" with no written link to Sub-Clause 13.1, which can cost the Contractor the notice clock, the valuation route, or both.
Template: Confirming a "Change Order" as a Variation Instruction
When an instruction arrives labelled as a change order, the fix is simple: confirm it back in FIDIC terms, in writing, promptly. This keeps the informal conversation and the binding instruction pointing at the same date.
This letter pins whatever the instruction was called on-site to the clause that protects the Contractor. Once sent, the date, description, and clause are all on record. Describing the instruction in plain language to ChatNotice works the same way — it drafts a Variation Claim notice under Sub-Clause 13.1/20.1 with the instruction date and clause already fixed.
Key Takeaway: Confirm any "change order" back to the Engineer in Sub-Clause 13.1 terms, in writing, close to the instruction date. That single letter converts an informal label into a protected contractual position.
Worked Example
On a data centre project under the FIDIC Yellow Book, the Employer's project director — used to AIA-form contracts — tells the site manager in a coordination call to add a secondary chilled-water loop to the mechanical design. She calls it "change order 14" in her follow-up email, without referencing any clause.
The Engineer's Representative does not object. Two months later, when the subcontractor's programme slips because of the added loop, the Contractor's Sub-Clause 20.1 notice for the consequential delay has an unambiguous instruction date to point to — 16 July 2026 — fixed by the confirmation letter, not an email thread that never mentioned the contract.
Key Takeaway: The worked example shows the pattern: whatever the instruction is called internally, confirm the Variation and its date in writing at the time. It is the confirmation, not the original label, that protects the Contractor later.
Common Mistakes
- Assuming the label doesn't matter. Shared understanding on-site is not the same as a written contractual instruction, and only the latter protects the Contractor in a dispute.
- Filing change order paperwork instead of a Sub-Clause 13.1 confirmation. An internal change order log is useful evidence, but it does not substitute for confirming the instruction against the actual clause.
- Letting the instruction date drift. If the change order was discussed informally before it was written down, the real instruction date can be earlier than the paperwork suggests.
- Forgetting the separate notice for consequential effects. The Clause 12 valuation covers the direct cost; delay it causes elsewhere on the programme usually still needs its own Sub-Clause 20.1 notice.
Key Takeaway: Most mistakes come from treating the informal label as if it were the contractual step. Confirm the instruction date, cite Sub-Clause 13.1 in writing, and send a separate notice for any consequential delay.
Frequently Asked Questions
Is a change order the same as a variation order under FIDIC?
Usually yes in substance, no in name. Both describe an instructed change to the Works, but FIDIC only defines and gives a procedure to the Variation, under Sub-Clause 13.1. "Change order" is not a FIDIC-defined term, so if that is the only label used, no contractual mechanism attaches to it until someone treats it as a Variation.
Does FIDIC use the term change order anywhere in the Conditions of Contract?
No. The FIDIC 1999 and 2017 Conditions of Contract use "Variation" throughout, defined in Sub-Clause 13.1 and valued under Clause 12. "Change order" is more common on North American forms such as the AIA A201, and it reaches a FIDIC project only through the habits of the people using it, not the contract wording.
If a project team uses change order paperwork on a FIDIC contract, which procedure applies?
The FIDIC procedure controls, regardless of what the internal paperwork is called. A change order form used informally does not replace a Sub-Clause 13.1 instruction or a Sub-Clause 20.1 notice. Treat it as evidence of the instruction, and still confirm it in FIDIC terms in writing.
Can a verbal change order still start the FIDIC Variation clock?
Yes. Under Sub-Clause 13.1, a Variation is defined by its effect on the Works, not by the label used or the form it arrives in. A verbal instruction that someone on site calls a "change order" can still be a Variation, and the notice clock runs from the date of that instruction.
Does it matter which term is used if the valuation ends up the same?
Yes, because the label affects which deadline and procedure a party can point to in a dispute. A Variation gives the Contractor a defined route to price adjustment, extension of time, and reasonable profit under Clause 12. A change order with no reference to the contract gives no such route on its own.
Authoritative Sources
This guide reflects the FIDIC Conditions of Contract and established construction-law authority. For the primary materials, see:
- FIDIC Conditions of Contract — the official contract suite published by the International Federation of Consulting Engineers, which defines the Sub-Clause 13.1 Variation procedure and its Clause 12 valuation route.
- SCL Delay and Disruption Protocol — the Society of Construction Law's widely used protocol on how instructed changes and their consequential delay effects should be evaluated and evidenced.
About the Author
Muhammad M. Jiwani is a Project Director with 15 years' experience on major infrastructure and energy projects administered under FIDIC contracts. He writes from first-hand experience serving notices and managing contractual claims on live projects.