FAR Part 43 Contract Modifications: A Federal Contractor’s 2026 Guide to Change Orders, Equitable Adjustments & REA

Table of Contents

• What FAR Part 43 Actually Governs and Why Every Contractor Must Understand It
• The 2025-2026 FAR Overhaul: What Changed for Part 43 and Why It Matters Now
• Federal Contract Change Orders: Rights, Obligations, and Traps
• Equitable Adjustment: What It Is, How Entitlement Is Established, and How to Calculate It
• REA vs. CDA Claim: The Decision Matrix Every Contractor Needs
• Building a Defensible REA: Recordkeeping, Cost Segregation, and DCAA Readiness
• Protecting Your Rights Throughout the Modification Process
• Frequently Asked Questions
•  Protecting Your Contract Rights in 2026

Most federal contractors absorb costs they’re legally entitled to recover. Not because the entitlement doesn’t exist. Because they don’t build the systems that prove it.
FAR Part 43 contract modifications govern every formal change to a federal contract: scope adjustments, price revisions, schedule relief, and the equitable adjustments that compensate contractors when the government changes the work. According to the Government Accountability Office, disputed contract modifications and underpaid equitable adjustments account for billions in unrecovered contractor costs annually. That number represents real margin walking out the door on active projects right now.
This guide covers what FAR Part 43 actually requires, how equitable adjustments and REAs work in practice, and where contractors consistently lose money they’ve earned. For the broader context on variation management across the full project lifecycle, see the federal contractor’s modifications guide before diving into the regulatory detail here.
The 2025 regulatory environment added new complexity: a freeze on pending FAR rules, updated cost-accounting guidance, and an administration actively restructuring how federal agencies award and administer contracts. Every federal contractor needs a current understanding of what the rules say, what’s changed, and what rights remain firmly in place.

What FAR Part 43 Actually Governs and Why Every Contractor Must Understand It

FAR Part 43 defines how contract modifications are issued, authorized, and priced on federal contracts. It covers bilateral and unilateral modifications, the changes clause, contracting officer authority, and the framework for equitable adjustments. Every federal contractor performing work under a prime contract or major subcontract operates inside this regulatory architecture whether they know it or not. How does FAR Part 43 define a contract modification? A contract modification is any written alteration in the specification, delivery point, rate of delivery, period of performance, price, quantity, or other provisions of a contract accomplished by mutual agreement or unilateral action in accordance with a contract clause.

The Legal Scope of the FAR Part 43 Changes Clause

The Changes clause (FAR 52.243-1 through 52.243-7 depending on contract type) is the engine driving modification rights. It gives the contracting officer unilateral authority to order changes within the general scope of the contract: changes to the work statement, inspection and testing requirements, delivery schedules, shipping methods, and site conditions. The clause simultaneously creates the contractor’s right to an equitable adjustment when those changes increase cost or time.
That right is not automatic. The Changes clause requires the contractor to assert the right: to notify the government, to document the impact, and to submit a price adjustment proposal within the timeframe the contract specifies. Contractors who perform the changed work and then fail to track and assert their entitlement forfeit the recovery. The clause is both a right and a responsibility.
Consider the construction variant specifically: FAR 52.243-4 governs fixed-price construction contracts and permits changes to the specifications, method or manner of performance, and accelerated completion. It’s a broad authority. Contractors who read it narrowly consistently underestimate how much changed work qualifies for adjustment.

Types of Contract Modifications: Bilateral vs. Unilateral

FAR Part 43 defines two fundamental modification types: bilateral and unilateral. Bilateral modifications, called supplemental agreements, require signatures from both parties and are used for definitized price changes, scope settlements, and no-cost modifications. Unilateral modifications are issued by the contracting officer alone and used to exercise options, make administrative changes, and issue change orders before price is settled.
Not a distinction without a difference. A bilateral modification signed by the contractor without protecting its right to equitable adjustment can extinguish future claims on the same issue. The SF-30 form used for all federal contract modifications carries legal weight: what you sign and what you exclude determines what you can recover later.
The best practice is reviewing every modification for release language before signing. Broad releases, such as phrases like “full and final settlement of all claims arising from,” can cut off entitlement on related but un-settled issues. Your contracts team should treat every bilateral modification as a partial claims waiver until confirmed otherwise.

Who Has Authority to Issue a Modification?

Only the Contracting Officer (CO) has authority to modify a federal contract. Not the Contracting Officer’s Representative (COR). Not a project engineer. Not a program manager. The CO alone holds the warrant that makes a modification legally binding.
This matters enormously in practice. When a COR or engineer directs changed work verbally or in writing, that direction is not a legal modification. It’s a potential constructive change: a government action that changes the contractor’s obligations without following the formal modification process. Contractors who perform directed changes from unauthorized personnel and then seek compensation face an uphill fight proving government liability.
Watch who is actually directing your field teams. If the instruction comes from anyone other than the CO on the contract, document it immediately, perform the work under protest if required, and notify the CO in writing. That paper trail is the foundation of your equitable adjustment claim.

The 2025-2026 FAR Overhaul: What Changed for Part 43 and Why It Matters Now

The risk for federal contractors in 2026 is not that FAR Part 43 has been gutted. It’s that many teams are operating on guidance that was suspended mid-implementation. A regulatory freeze in early 2025 halted pending FAR revisions, left agency supplements partially updated, and created a gap between what contractors expect the rules to say and what contracting officers are actually applying at the activity level.

The Trump Administration’s 2025 Regulatory Freeze and RFO Third Tranche

Executive Order 14219, issued in February 2025, froze pending federal regulations across agencies including DoD and civilian procurement offices. Several FAR rule changes that were in public comment or final-rule stages were suspended, including updates to small business subcontracting plans and some cost-principle clarifications. The FAR Council’s Regulatory Freeze Order (RFO) Third Tranche specifically identified Part 43-adjacent rules on undefinitized contract actions and equitable adjustment procedures that remain in regulatory limbo as of May 2026.
The practical consequence: contracting officers are applying pre-freeze interpretations of modification procedures. Contractors should not assume that guidance issued between mid-2024 and early 2025 has been fully implemented at the contracting activity level. Verify current agency-specific supplements, particularly DFARS for defense contracts and HHSAR for health agency contracts, before relying on any procedural updates from that window.
Picture a mid-tier defense contractor who assumed a pending DFARS update on definitization timelines had taken effect, only to find the contracting officer applying the older 180-day standard. The resulting undefinitized contract action dragged for seven months before a formal modification issued. The lesson: confirm the applicable regulatory version with the contracting office before negotiations begin.

What Has NOT Changed: Stable Anchors Contractors Can Rely On

The core framework of FAR Part 43 is stable. The Changes clause, the bilateral and unilateral modification structure, the SF-30 form, contracting officer warrant requirements, and the equitable adjustment entitlement framework remain unchanged. The Contract Disputes Act (CDA) claim procedures, the 6-year statute of limitations, the certification requirement for claims over $100,000, and the Armed Services Board of Contract Appeals and Court of Federal Claims appeal processes are all intact.
These are the load-bearing walls of federal contract modification law. The regulatory activity of 2025 was largely concerned with acquisition policy and socioeconomic program requirements, not the fundamental mechanics of how modifications are issued and priced. Contractors who understand the core framework are not exposed to the regulatory uncertainty affecting other areas.

Practical Adjustments Contractors Should Make in 2026

Ask your contracts team to verify three things at the outset of every new contract award: which Changes clause variant applies, what the agency supplement adds to the base FAR requirements, and what the contracting officer’s warrant limit is. Those three data points shape every modification negotiation that follows.
Rather than waiting for a CO to raise modification issues, build a proactive modification tracking system from contract award. The contractors who recover the most on equitable adjustments are not the ones with the best lawyers. They’re the ones with the best contemporaneous records.

Federal Contract Change Orders: Rights, Obligations, and Traps

Federal contract change orders are not requests. They’re directives. When a contracting officer issues a change order under the Changes clause, the contractor is legally obligated to perform the changed work, even if price is not yet agreed. That obligation is the source of significant financial risk for contractors who don’t manage the process from day one. Understanding federal contractor change order rights is not optional for any business holding a government prime contract.
For a broader look at how U.S. general contractors structure their variation management systems, see how U.S. GCs manage change orders in 2026. The parallels between commercial and federal practice are instructive even where the legal frameworks differ.

When Is a Contractor Required to Perform Before the Price Is Settled?

The short answer: almost always. The Changes clause gives the government the right to order changes and requires the contractor to proceed with performance while the equitable adjustment is negotiated. This is the “duty to proceed” doctrine. Refusing to perform a directed change, even a disputed one, can constitute a default and expose the contractor to termination for cause.
The correct response to a disputed change order is not refusal. It’s documented compliance under protest. Perform the work. Track the costs separately. Submit a written notice to the CO asserting that the change exceeds the contract scope or that the cost impact has not been agreed. That notice preserves your right to pursue an equitable adjustment or, if necessary, a CDA claim.
Evaluate the cost implications of every change before you begin the changed work, not after. A contractor who commingles changed-work costs with base-contract costs loses the ability to segregate them later, and an unsegregated cost claim is a weak cost claim. The machinery of recovery starts on day one of changed work performance.

Constructive Changes: When the Government Changes the Work Without Calling It a Change

FAR 43 constructive changes are the most underutilized recovery avenue in federal contracting. A constructive change occurs when the government imposes additional obligations on the contractor through actions that are not formally labeled as change orders: defective specifications that require rework, over-inspection that exceeds the contract standard, acceleration orders that compress the schedule, and oral directions from unauthorized personnel that change the scope.
Not a technicality. It’s a well-established doctrine recognized by both the Armed Services Board and the Court of Federal Claims, with decades of decisions affirming contractor recovery. The challenge is that constructive changes require the contractor to recognize them, document them, and assert them; the government won’t volunteer the entitlement.
Consider a facilities contractor performing a DoD building renovation. The government inspector required installation methods that went beyond the specification’s stated standard, adding 340 labor hours to the finishing phase. The specification was defective. The inspector’s requirements constituted a constructive change. The contractor documented the impact, notified the CO in writing, and recovered $87,000 in equitable adjustment. The recovery existed only because someone on the team recognized the constructive change pattern in real time.

Cardinal Change: When a Modification Exceeds Scope and Voids the Contract

The Changes clause gives the government broad but not unlimited authority. A cardinal change is a modification so significant that it fundamentally alters the nature of the contract, effectively ordering a different contract than the one awarded. Cardinal changes are not enforceable under the Changes clause, and a contractor who performs cardinal-change work is not bound by the original contract’s pricing structure.
Cardinal change is a legal conclusion, not a simple metric. Courts look at whether the change materially differs from what was bargained for: a dramatic increase in quantity, a complete change in the type of work, or a combination of changes that transforms the contract’s character. Rather than invoking cardinal change lightly, contractors should use it as the framework for a larger equitable adjustment claim when accumulated changes have fundamentally altered their performance obligations.

Equitable Adjustment: What It Is, How Entitlement Is Established, and How to Calculate It

An equitable adjustment under FAR Part 43 is a contract price and schedule modification compensating a contractor for government-caused cost increases or time impacts. It covers direct costs, indirect costs, and profit on the changed work, applied as a bilateral modification issued after negotiation. The adjustment must reflect the actual impact of the change: neither more nor less than what a fair, reasonable, and documented calculation supports. Specifically, the adjustment equals the difference between what it would have cost to perform the original work and what it costs to perform the changed work, plus profit at the applicable weighted guidelines rate.

The Three-Part Entitlement Test (Liability, Causation, Damages)

Every equitable adjustment federal contract claim rests on three elements. Liability: the government is responsible for the changed condition or direction under the contract terms. Causation: the government’s action directly caused the cost increase or schedule impact the contractor experienced. Damages: the contractor can quantify the actual costs incurred as a result of the government’s action.
Fail any one of these three and the equitable adjustment claim fails. The best claims are the ones where all three elements are documented independently: a written direction from the CO establishes liability, a time-coded cost segregation report establishes causation, and DCAA-compliant cost records establish damages. Rather than building the claim after the fact, build it contemporaneously as the changed work proceeds.
Ask yourself at every stage of changed work: can I connect this dollar to this government direction? If the answer is no, you have a documentation gap that will cost you in negotiations. The government’s auditors are experts at finding those gaps. Your job is to close them before the REA is submitted.

Allowable, Allocable, and Reasonable Costs Under FAR Part 31

Equitable adjustments are priced using FAR Part 31 cost principles. Not every cost incurred on changed work is recoverable: costs must be allowable (not expressly prohibited by FAR 31.205), allocable (properly assigned to the changed work using a consistent methodology), and reasonable (not exceeding what a prudent person would pay in a competitive market).
Common unallowable costs that contractors mistakenly include: entertainment, interest on borrowings, certain bid and proposal costs allocated incorrectly, and executive compensation above CAS-established limits. Including unallowable costs in an REA or CDA claim doesn’t just result in those costs being disallowed. It creates credibility problems for the entire submission and can trigger a DCAA review of the contractor’s broader accounting practices.
The best approach is a pre-submission cost scrub against FAR 31.205 before any REA leaves your office. That scrub should be documented. The documentation demonstrates good faith to the contracting officer and reduces DCAA exposure during field pricing review.

Time Extensions: Don’t Leave Schedule Relief on the Table

Equitable adjustments include schedule relief, not just money. When a change order delays performance, the contractor is entitled to an extension of the contract completion date, which in turn relieves liability for liquidated damages during the extended period. Liquidated damages on federal construction contracts routinely run $1,000 to $5,000 per day, making schedule relief worth as much as the direct cost recovery in many modifications.
Rather than negotiating cost and schedule separately, integrate both into every equitable adjustment proposal from the start. Prove the critical path impact using your project schedule, document the delay days attributable to each change, and tie the schedule extension request directly to the cost impact. Separating cost from schedule is a mistake that leaves contractors exposed to LD assessments they’ve already earned relief from.

REA vs. CDA Claim: The Decision Matrix Every Contractor Needs

An REA is a pre-dispute negotiation proposal. A CDA claim is a certified demand triggering formal government response rights and appeal procedures. The request for equitable adjustment REA preserves the relationship with the contracting officer and avoids certification mechanics, while the CDA claim starts interest accrual from the date of submission and opens the door to ASBCA or COFC appeal if the CO denies or ignores it. Choosing the right instrument at the right time is one of the highest-value decisions a federal contractor makes in any modification dispute. An REA converted to a CDA claim on a $3 million dispute, for example, accrues interest at the Treasury rate (currently approximately 5.25%) from the date of the original CDA submission.

What Is a Request for Equitable Adjustment (REA)?

A request for equitable adjustment REA is a formal proposal submitted to the contracting officer requesting a modification to the contract price, schedule, or both, based on a government-caused change. It is not a claim under the Contract Disputes Act. It doesn’t require certification. It doesn’t accrue interest. It’s a business negotiation supported by documented cost and schedule impact, making it the preferred first step in resolving modification disputes.
The REA format is not legally prescribed by FAR, but best practice follows the structure of a CDA claim: statement of the facts, legal entitlement analysis, cost impact documentation, and schedule impact analysis. A well-structured REA is not just a negotiation document. It’s the foundation for a CDA claim if negotiations fail. Build it once, build it right.

What Is a Certified CDA Claim and When Does It Become Necessary?

A CDA claim is a written demand for a contracting officer’s final decision (COFD) on a contractor’s right to payment or other contract relief. Claims exceeding $100,000 require certification under 41 U.S.C. § 7103: the contractor’s authorized representative must certify that the claim is made in good faith, that the supporting data is accurate and complete to the best of their knowledge, and that the amount requested accurately reflects what the contractor believes is owed.
The CDA claim becomes necessary when an REA is denied, ignored for an unreasonable time, or when the statute of limitations is approaching. The 6-year CDA statute of limitations runs from when the contractor knew or should have known the facts giving rise to the claim. Missing it is fatal. Not a procedural technicality. An expired CDA claim is an unrecoverable loss.

The REA-vs.-CDA Decision Matrix

How to Submit a Request for Equitable Adjustment: Step by Step

Step one: identify the entitlement basis. Confirm which Changes clause provision applies and that the event you’re claiming falls within its scope. Step two: segregate the costs. Pull together all direct labor, material, equipment, and subcontract costs specifically attributable to the changed work, coded separately in your accounting system from the base contract. Step three: calculate indirect costs. Apply your established overhead and G&A rates consistently with your disclosed accounting practices.
Step four: build the narrative. Write a clear statement of facts that ties the government’s direction to your performance impact without exaggeration or legal advocacy. Step five: calculate schedule impact. Produce a critical path analysis showing which changed activities delayed contract completion and by how many days. Step six: prepare and submit a formal proposal letter to the CO, attaching all supporting documentation and requesting a bilateral modification.
For a detailed procedural template, the Request for Equitable Adjustment workflow covers each step with format guidance and common submission errors to avoid.

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Building a Defensible REA: Recordkeeping, Cost Segregation, and DCAA Readiness

An REA is only as strong as the records behind it. The contracting officer reviewing your submission and the DCAA auditor assigned to field pricing are both trained to identify documentation gaps, unsupported cost assertions, and inconsistencies between claimed costs and your disclosed accounting system. The difference between a fully recovered REA and a substantially reduced one is almost always recordkeeping quality.

Why Contemporaneous Records Are the Foundation of Every Successful REA

Contemporaneous records are records created at the time of the event: daily reports documenting who worked where and on what, material delivery receipts tied to specific work items, subcontractor invoices coded to change-order work, and correspondence with the CO and COR documenting directions and disagreements. Records reconstructed after the fact are not contemporaneous. They’re reconstructions, and DCAA knows the difference.
Rather than treating recordkeeping as an administrative burden, treat it as a revenue protection function. A contractor who maintains complete daily logs on a $15 million federal construction contract creates the evidentiary foundation for full recovery on every change order that follows. One who doesn’t is negotiating from a position of weakness on every single modification.
Picture a mechanical contractor on a VA hospital renovation who maintained daily foreman logs tied to individual work packages. When a series of government-directed acceleration orders compressed the schedule by six weeks, the contractor’s contemporaneous records documented exactly which crews were impacted, which overtime hours were incurred, and which subcontractors received acceleration premiums. The REA recovered $1.2 million. The records made it possible.

How DCAA Field Pricing Reviews Work and What Triggers One

DCAA field pricing reviews are triggered on REAs and change order proposals above certain thresholds, currently $2 million for most agency contracts, though DFARS contracts can trigger review at lower amounts. The DCAA auditor examines whether your claimed costs are allowable under FAR Part 31, whether your cost accounting practices are consistent with your CAS disclosure statement, and whether the costs are properly allocated to the changed work rather than the base contract.
DCAA is not the enemy. It’s a structured process with predictable criteria. Contractors who prepare for a DCAA review as a standard part of every REA submission, rather than treating it as an adversarial intrusion, consistently achieve better outcomes. The auditors are looking for documentation, consistency, and compliance. Give them those three things and the review becomes a validation rather than a reduction exercise.

A Pre-Submission DCAA-Readiness Checklist

Before submitting any REA above $500,000, verify the following:

• All claimed direct costs are coded to a dedicated change-order work breakdown structure element in your accounting system
• Overhead and G&A rates applied are consistent with your most recent DCAA-approved forward pricing rate agreement
• Unallowable costs have been identified and excluded, with documentation of the exclusion decision
• Subcontractor costs are supported by lower-tier REAs or invoices with equivalent documentation
• All contemporaneous records (daily logs, correspondence, schedule updates) are compiled and indexed
• The cost narrative in the REA matches the accounting records dollar-for-dollar
• Profit rate is justified with reference to the weighted guidelines method or agency-specific approach

Protecting Your Rights Throughout the Modification Process

The government contract modifications process has built-in deadlines, procedural requirements, and rights that expire if not exercised. Most of the money federal contractors leave on the table is not lost in negotiation. It’s forfeited before negotiation begins: through missed notice requirements, unsigned modifications with overbroad releases, and undefinitized contract actions that dragged past the definitization deadline without a pricing proposal.
For a reference guide to the full procedural framework, the FAR Part 43 federal change order playbook covers notice requirements, definitization timelines, and flow-down obligations with practical checklists for each stage.

Notice Requirements: Why Missing a Deadline Can Forfeit Your Recovery

The Changes clause requires contractors to provide notice of a changed condition or constructive change within a specified period, typically 20 days of when the contractor knew or should have known of the change. Some contracts specify shorter windows. Missing the notice deadline doesn’t automatically forfeit the claim in all jurisdictions, but it creates a strong government defense and puts the burden on the contractor to show the government wasn’t prejudiced by the late notice.
Rather than relying on a prejudice argument, which is inherently uncertain, build a notice protocol into your change management process from day one. Any field condition, government direction, or specification conflict that could affect cost or schedule gets a written notice to the CO within 48 hours. Overcommunicating is not a risk. Undercommunicating is.
Federal contractor change order rights are only meaningful if they’re exercised in time. A timely notice is the gate that all subsequent recovery must pass through. Without it, even a well-documented, legally sound equitable adjustment claim faces a procedural hurdle that costs money to overcome and sometimes can’t be overcome at all.

Definitization: Turning an Undefinitized Contract Action Into a Settled Modification

An undefinitized contract action (UCA) is an authorization to begin work before price is settled, common in urgent or fast-moving federal projects. FAR 43.102 and DFARS 217.74 require definitization within 180 days of the UCA issuance or before 40% of the estimated cost is incurred, whichever comes first. Missing the definitization deadline exposes the contractor to increased government scrutiny of pricing and can limit profit recovery.
The government’s leverage in definitization negotiations is real but not absolute. Once a UCA is issued and work is underway, both parties have incentive to settle on price. The contractor’s leverage is its cost records: a contractor with detailed contemporaneous records and a well-documented forward pricing proposal settles UCAs faster and at better rates than one scrambling to reconstruct costs at the negotiating table.

Protecting Subcontractor and Small Business Flow-Down Rights

Prime contractors have an obligation to flow down the Changes clause and equitable adjustment rights to subcontractors who perform changed work. Failure to flow down creates two problems: the prime is exposed to subcontractor claims that it can’t pass through to the government, and the small business subcontractor is deprived of legal rights the FAR intends to protect.
The best prime contracts include a flow-down matrix that maps every FAR clause required to appear in subcontracts and assigns responsibility for tracking compliance to the subcontracts team. Rather than addressing flow-down at dispute resolution time, address it in the subcontract template before the first purchase order is issued. That upstream investment eliminates a category of downstream exposure entirely.

Frequently Asked Questions

What is an equitable adjustment under FAR Part 43?

An equitable adjustment under FAR Part 43 is a modification to a federal contract’s price, schedule, or both, compensating the contractor for government-caused cost increases or delays. It covers allowable direct and indirect costs plus profit on the changed work, and is triggered by a formal change order, constructive change, or differing site condition. The government owes it; the contractor must claim it.
Entitlement to an equitable adjustment requires establishing three elements: that the government is liable for the changed condition, that the government’s action caused the contractor’s increased costs or delays, and that the contractor can document and quantify those damages using FAR Part 31-compliant cost records. All three must be present. A claim that proves two of three elements is a claim that recovers partial value at best.

What is the difference between a change order and a contract modification under FAR?

A change order is a unilateral modification issued by the contracting officer directing the contractor to change the work before price is agreed. A contract modification is any written alteration to a contract’s terms, including change orders, bilateral supplemental agreements, administrative changes, and option exercises. Every change order is a modification, but not every modification is a change order.
The distinction matters because a bilateral modification, signed by both parties, can include release language that waives future claims on related issues. A unilateral change order does not extinguish the contractor’s right to propose and negotiate an equitable adjustment. Understanding which type of document you’re being asked to sign is foundational to protecting your rights throughout the government contract modifications process.

How long does a contractor have to submit an REA or equitable adjustment request?

The FAR Changes clause typically requires notice within 20 days of when the contractor knew or should have known of the change. The REA itself has no statutory deadline, but CDA claims must be filed within 6 years of claim accrual. Waiting to submit an REA increases the risk that contemporaneous records degrade and CO turnover disrupts institutional knowledge of the facts.
In practice, the best approach is to submit an REA as soon as the changed work scope and cost impact can be documented with reasonable precision, typically within 60 to 90 days of completing the changed work. Delay benefits no one on the contractor’s side and gives the government grounds to assert prejudice from late notice. The 6-year CDA statute is not a planning horizon. It’s an absolute backstop for claims that couldn’t be resolved earlier.

Can a contractor refuse to perform a change order?

A contractor cannot refuse a change order that falls within the general scope of the contract without risking default termination. The duty to proceed requires performance of directed changes while price is negotiated. The correct response to a disputed change order is documented performance under protest, with simultaneous written notice to the CO preserving equitable adjustment rights.
The exception is a cardinal change: a modification so extreme that it fundamentally alters the nature of the contract. A cardinal change exceeds the government’s authority under the Changes clause, and a contractor who refuses to perform it, with proper legal support, is not in default. But invoking cardinal change is a legal strategy requiring careful analysis, not a routine dispute tactic.

What is the difference between an REA and a CDA claim?

An REA is a pre-dispute negotiation proposal requesting a contract modification, requiring no certification and accruing no interest. A CDA claim is a certified demand for a contracting officer’s final decision, which starts interest accrual from the claim date and opens appeal rights to the ASBCA or COFC if the CO denies or fails to decide within the statutory period. The REA keeps the dispute in negotiation mode; the CDA claim escalates it to an adversarial posture.
Most contractors start with an REA and convert to a CDA claim only when the CO denies the REA, ignores it for an unreasonable period, or when the 6-year statute of limitations is approaching. The two are not mutually exclusive; a well-drafted REA becomes the factual foundation for the CDA claim if negotiations fail. Build the REA as if a CDA claim will follow. It often does.

Next Steps: Protecting Your Contract Rights in 2026

FAR Part 43 contract modifications don’t resolve themselves in the contractor’s favor by default. The regulatory framework creates rights, but exercising those rights requires systems: notice systems, cost-tracking systems, documentation systems, and negotiation systems that operate from contract award through final modification settlement. Contractors who build those systems recover what they’re owed. Those who don’t absorb the loss.

Build Your Modification Management System Before You Need It

The modification management system is not a reaction to disputes. It’s a contract administration infrastructure built at award and operated continuously throughout performance. It includes a change log updated in real time, cost segregation codes in your accounting system assigned before changed work begins, a notice calendar tied to contract-specific deadlines, and a modification review process for every SF-30 before signature.
Rather than treating change management as a project-level responsibility, assign ownership at the corporate level and require consistent implementation across all active contracts. A single modification management framework applied to a portfolio of federal contracts creates compounding value: every lesson from one REA improves the next, and documentation quality improves with each contract cycle.

When to Bring in Outside Help

Bring in outside counsel or claims consultants when the equitable adjustment exceeds $500,000 and DCAA field pricing is likely, the CO has denied an REA and a CDA claim is being considered, the modification involves a complex constructive change or cardinal change argument, or the 6-year CDA statute of limitations is within 12 months of expiring on a significant claim.
Honest concession: outside help costs money. A claims consultant on a $2 million REA may cost $80,000 to $150,000 in fees. But a poorly structured $2 million REA that recovers 40 cents on the dollar costs $1.2 million in foregone recovery. The right question is not whether you can afford outside help. It’s whether you can afford to manage a complex federal modification dispute without it.

How Sinq Can Support Your Contract Modification Workflow

Most federal contractors track their active modifications across a mix of shared spreadsheets, email folders, and project tools that were never built for this purpose. Notice deadlines get missed by days. Costs commingle with base-contract work. An REA gets assembled from reconstructed records six months after the changed work closed. That’s not a documentation problem. It’s a systems problem.

Sinq solves it. Change log, cost segregation codes, notice deadline tracking, and REA documentation in a single platform that produces submission-ready output from the moment a change order is issued, rather than the week before negotiations begin.
For federal contractors managing multiple active contracts with concurrent modification disputes, Sinq eliminates the fragmentation problem: each project team managing modifications differently, records stored in disconnected systems, and the corporate contracts function unable to see a current view of exposure across the portfolio. That fragmentation is where recovery falls apart. Sinq replaces it with a structured workflow that keeps every modification on track from direction to settlement.
Rights on paper don’t protect revenue. Systems do.Ready to stop managing modifications in tools that weren’t built