Brief
A defense contract's type is not a formality. It is the mechanism that decides who owns the financial consequence of a program running over budget, and it is chosen at the moment of award, not adjusted after the fact except through formal modification. On one end of the spectrum sits cost-plus-fixed-fee (CPFF), where the government agrees to reimburse the contractor for allowable, allocable, and reasonable costs and pay a fee set at contract signing that does not change with cost performance. On the other end sits firm-fixed-price (FFP) and commercial-item contracting, where the contractor is paid one agreed price regardless of what the work actually costs them to perform. In between sits fixed-price-incentive (FPI), which uses a formula, a target cost, a target profit, a ceiling price, and a share ratio, to split cost overruns and underruns between government and contractor up to a defined breakpoint.
The reason this spectrum exists is that risk allocation and price uncertainty move in opposite directions. When the government cannot define the work precisely at the outset (early-stage research, a first-of-kind development effort, an unproven technology), a contractor asked to commit to a fixed price has to build in a large contingency buffer to protect against unknowns it cannot control, or it declines to bid. Cost-reimbursement contracting solves that problem by having the government absorb the unknown-cost risk in exchange for real-time visibility into the contractor's books. When the work is well-defined and repeatable, that visibility is unnecessary and a fixed price is more efficient, because the contractor, not the government, is best positioned to manage a known scope of work at a known cost. The government's own guidance now states this directly: Federal procurement has tolerated unpredictable costs, bloated overhead, and weak performance incentives, and the government must adopt best business practices to protect taxpayer dollars and achieve demonstrable returns on investment, framing fixed-price mechanisms as the corrective.
Whatever contract type is chosen, oversight scales with how much of the cost risk the taxpayer still carries. Cost-reimbursement contracts require the contractor's accounting system to survive government audit because every dollar billed is a claim against actual incurred cost: an incurred cost audit helps assess the accuracy of a contractor's annual costs and determines whether the costs are allowable, reasonable, and allocable, and FAR 52.216-7 requires an annual Incurred Cost Submission, which DCAA samples and tests back to source documents for compliance with FAR Part 31. Above a dollar threshold, contracts also carry Cost Accounting Standards (CAS) coverage, a separate and more rigid layer requiring the contractor to disclose and consistently apply its cost accounting practices; this threshold has itself just moved. Under the FY2026 NDAA, the Truthful Cost or Pricing Data threshold rises from $2.5 million to $10 million, and the contract-level threshold for mandatory CAS application rises from $2.5 million to $35 million, for contracts awarded on or after June 30, 2026, while the historical $7.5 million trigger-contract mechanism is eliminated. Firm-fixed-price and commercial-item contracts largely escape this entire audit apparatus, because the government has no cost-reimbursement exposure to police: firm-fixed-price contracts awarded on the basis of adequate price competition without submission of certified cost or pricing data, and commercial items under FAR Part 12, are categorically exempt from CAS. This is the structural trade the whole system rests on: the government buys either cost transparency (and pays for the audit apparatus that comes with it) or price certainty (and gives up visibility into the contractor's actual costs).
The system is currently under active policy pressure to shift the default toward the fixed-price end. Executive Order 14402, signed April 30, 2026, states that fixed-price contracts with performance-based considerations should serve as the default and preferred method of procurement, to the maximum extent consistent with law, and is critical of cost-reimbursement contracting, stating those arrangements can involve poorly defined deliverables and expose the government to overspending, aiming to shift more cost risk to contractors. The order does not just set a preference; it builds an enforcement mechanism. If a non-fixed-price contract exceeds thresholds defined in the order, the agency head must approve it in writing, and agency heads must review and, to the maximum extent practicable, modify, restructure, or renegotiate their 10 largest non-fixed-price contracts within 90 days of the order. Those thresholds are set agency by agency, with the Department of War (the department historically called Defense) carrying the highest ceiling before requiring agency-head sign-off, reflecting that complex weapons development is where cost-reimbursement contracting is most defensible on the merits and hardest to eliminate by fiat.
None of the contract types is free of a structural failure mode, and the failure modes are mirror images of each other. Cost-reimbursement contracting is prone to cost growth with weak contractor incentive to control it, since the fixed fee does not shrink when costs rise, sometimes called the moral hazard of cost-plus work. Fixed-price contracting on genuinely uncertain or immature work is prone to the opposite failure: a contractor that underbid to win the contract either absorbs a loss it cannot sustain, cuts corners on quality or scope to protect margin, or returns later seeking a contract modification that partially restores the cost protection the fixed price was supposed to eliminate. Fixed-price-incentive contracting sits in the middle and is prone to a subtler failure, the Point of Total Assumption: the cost level at which the contractor begins absorbing 100% of all further overruns, because the ceiling price has effectively been reached; beyond the PTA, the FPI contract functions like a firm-fixed-price contract, which means the incentive structure that was supposed to align contractor and government interests collapses precisely at the moment costs are running highest and program pressure is greatest.
Components (8)
Cost-Plus-Fixed-Fee (CPFF) contract
The government reimburses allowable, allocable, reasonable incurred costs and pays a fee fixed at award that does not vary with actual cost performance, used when the work cannot be priced with confidence at the outset.
Fixed-Price-Incentive-Firm (FPIF) contract
Sets a target cost, target profit, target price, ceiling price, and a share ratio; both parties split cost overruns and underruns according to the share ratio up to the Point of Total Assumption, after which the contractor bears all further overrun alone up to the ceiling.
Firm-Fixed-Price (FFP) contract
Sets a single price not adjusted for the contractor's actual cost experience; FAR Part 16 defines this as a price that is not subject to any adjustment on the basis of the contractor's cost experience in performing the contract.
Commercial-item contract (FAR Part 12)
Applies fixed-price-style terms to items or services of a type customarily sold in the commercial marketplace, exempting the contract from certified cost-or-pricing-data requirements and CAS coverage on the theory that market competition, not government audit, disciplines the price.
Defense Contract Audit Agency (DCAA)
Audits contractor incurred-cost submissions and accounting systems on cost-reimbursement contracts to verify costs billed are allowable, allocable, and reasonable under FAR Part 31; has no audit reach into firm-fixed-price or commercial subcontracts.
Cost Accounting Standards (CAS) coverage
A separate, more rigid disclosure-and-consistency regime layered on top of cost-reimbursement and large negotiated contracts above a dollar threshold, requiring contractors to disclose and consistently follow their cost accounting practices across all their government work.
Point of Total Assumption (PTA) mechanism
The formula-derived cost level within an FPIF contract at which the contractor's share of further cost overrun jumps from the negotiated ratio to 100%, converting the contract's remaining risk allocation to look like a firm-fixed-price arrangement.
Executive Order 14402 approval-and-review structure
The current policy layer forcing agency heads to justify, in writing, any non-fixed-price contract above an agency-specific dollar threshold, and to review and attempt to renegotiate the ten largest existing non-fixed-price contracts toward fixed-price terms.
How It Works (8 steps)
1Requirement defined and contract type selected
The program office and contracting officer assess how well the technical scope is understood and how much cost uncertainty exists, then select a contract type from the FAR Part 16 spectrum matched to that uncertainty.
Program managerContracting officer
Why this step: Selecting the wrong contract type for the actual level of technical uncertainty is the single most common structural error in acquisition, since a fixed price on immature technology forces the contractor to either overprice for risk or absorb losses later.
2Cost or pricing data submitted and negotiated
Above the applicable dollar threshold, the contractor certifies cost or pricing data supporting its proposed price; under the FY2026 NDAA revision, that certification threshold rises from $2.5 million to $10 million for contracts awarded on or after June 30, 2026. The contracting officer negotiates target cost, fee, and (for FPIF) the ceiling price and share ratio.
Contractor pricing/estimating teamContracting officerDCAA (if requested to review the proposal)
Why this step: Without this negotiation, neither party has a documented basis for what the price or target cost should be, making later cost-growth disputes unresolvable.
3CAS coverage and accounting-system adequacy determined
The contracting officer determines whether the contract is CAS-covered based on dollar value and contractor status; under the FY2026 threshold change, contracts below $35 million are generally exempt from mandatory CAS application, while firm-fixed-price contracts awarded on adequate price competition and commercial items remain categorically exempt regardless of value.
Contracting officerDCAA or cognizant federal agencyContractor's accounting department
Why this step: CAS coverage determines whether the contractor must disclose and consistently apply its cost accounting practices across all its government work, not just this contract, materially raising compliance burden for cost-type awards.
4Performance begins and cost/price mechanism activates
On CPFF contracts, the contractor bills actual allowable costs plus the fixed fee as work proceeds. On FPIF contracts, the contractor is paid at negotiated progress rates against the target price while actual costs accumulate against the target cost. On FFP and commercial contracts, the contractor is paid the agreed price on delivery or milestone regardless of its internal cost experience.
ContractorContracting officer's representativeDCAA (cost-type contracts only)
Why this step: This is the point where the risk allocation chosen at award actually starts to bite: cost growth on a CPFF contract flows to the taxpayer's bill, while cost growth on an FFP contract flows to the contractor's margin.
5Incurred costs audited annually (cost-reimbursement contracts only)
Contractors performing cost-reimbursement work file an annual Incurred Cost Submission, which DCAA samples and tests against source documents for compliance with FAR Part 31 allowability rules; DCAA has shifted to risk-based sampling that exempts lower-risk, lower-dollar submissions from full audit.
ContractorDCAA
Why this step: This audit is the only mechanism verifying that costs billed to the government on a cost-type contract were actually allowable, allocable, and reasonable rather than padded or misallocated; it does not exist for FFP or commercial contracts because there is no cost-reimbursement claim to verify.
6FPIF share-ratio and PTA mechanics apply as costs diverge from target
As actual costs run above or below the negotiated target cost, the share ratio splits the variance between government and contractor up to the ceiling price. If actual costs reach the Point of Total Assumption, the contractor absorbs all further cost growth dollar-for-dollar until the ceiling price is hit, after which the contractor is in a loss position on every additional dollar spent.
Contracting officerContractor program managerContractor finance/EVM team
Why this step: This is the formula that is supposed to keep contractor incentives aligned with cost control across the full range of possible outcomes; when a program is tracking toward or past the PTA, the shared-risk incentive collapses into pure fixed-price exposure for the contractor, sharply changing its behavior.
7Final price or fee settled at contract closeout
On CPFF contracts, final indirect cost rates are trued up through DCAA's incurred-cost audit and closeout. On FPIF contracts, the final price is calculated from actual costs against the negotiated formula, capped at the ceiling price. FFP and commercial contracts require no cost-based settlement since the price was fixed at award.
Contracting officerDCAAContractor
Why this step: Closeout is where the risk allocation chosen in step one is finally realized in dollars — the taxpayer's final bill on a CPFF contract, or the contractor's final margin on an FFP or FPIF contract past target.
8Agency-level review and justification under current policy pressure
Under Executive Order 14402, agencies must justify in writing any new non-fixed-price contract above agency-specific thresholds and must have reviewed their ten largest existing non-fixed-price contracts for possible renegotiation toward fixed-price terms within 90 days of the order.
Agency headContracting officerOMB (recipient of semi-annual compliance reports)
Why this step: This step exists because the government has determined, at a policy level, that too much of the portfolio still carries cost-reimbursement risk, and it is using an approval gate rather than a blanket ban to force case-by-case justification.
Where It Breaks (4)
Cost-reimbursement contract cost growth with muted contractor incentive to control it
Consequence: Program costs escalate beyond the original estimate, and because the fixed fee does not scale down and the government is contractually obligated to reimburse allowable costs, the primary corrective is renegotiation, incurred-cost audit disallowances, or program restructuring rather than contractor absorption of the overrun.
Safeguard: DCAA incurred-cost audits and CAS disclosure requirements constrain what costs can be billed, but they audit allowability and allocability, not whether the total cost was reasonable to incur in the first place.
Fixed-price award on immature or poorly defined technical work
Consequence: A contractor that underbid to win a firm-fixed-price or FPIF award either absorbs an unsustainable loss, cuts scope or quality to protect margin, or later seeks a contract modification (a request for equitable adjustment or claim) that partially restores cost protection the fixed price was meant to eliminate.
Safeguard: Contracting officers are supposed to match contract type to technical maturity per FAR Part 16 guidance; EO 14402's push toward fixed-price defaults raises the risk this match gets overridden by policy pressure rather than technical judgment.
FPIF incentive collapse at the Point of Total Assumption
Consequence: Once actual costs cross the PTA, the contractor bears all further overrun dollar-for-dollar up to the ceiling price, which can trigger reduced contractor investment in problem-solving exactly when program cost pressure and government attention are highest, and can precipitate disputes over whether cost growth was contractor-caused or government-caused (which affects who legally bears it).
Safeguard: Program offices are expected to track actual cost against target cost and flag approaching PTA as an early-warning indicator, but this depends on timely earned-value or cost-performance reporting.
CAS threshold and coverage gaps creating audit blind spots
Consequence: Raising the CAS mandatory-coverage threshold from $2.5 million to $35 million (effective for contracts awarded on or after June 30, 2026) exempts a large population of mid-size negotiated contracts from consistent cost-accounting-practice disclosure, which could allow inconsistent cost allocation practices across a contractor's book of business to go undetected on contracts just below the new threshold.
Safeguard: Modified CAS coverage and DCAA's risk-based incurred-cost sampling are intended to concentrate audit resources on higher-risk or higher-dollar contractors, but this is a resource-allocation choice, not a guarantee that gaps below threshold are actually low-risk.
The claims behind this analysis, each with its verification status — including what is contested, unverified, or could not be established.
What each grade meansThe share ratio and Point of Total Assumption in FPIF contracts — The share ratio splits cost variance between government and contractor within a bounded range, but the PTA formula, driven by ceiling price, target price, and the buyer's share ratio, marks the exact point where that shared incentive converts to full contractor liability, functioning as a built-in escalation trigger for program risk attention.
✓ DOCUMENTED
CAS disclosure-and-consistency requirement as a proxy for cost-reimbursement exposure — CAS coverage exists specifically to police cost allocation across a contractor's full book of government work wherever the government is exposed to actual-cost reimbursement; the FY2026 threshold increase to $35 million for mandatory CAS application shrinks the population of contracts subject to this deeper scrutiny, concentrating it on the largest cost-type awards.
✓ DOCUMENTED
Fixed-fee invariance on CPFF contracts as the source of weak cost-control incentive — Because the fee on a CPFF contract is set at award and does not change with cost performance, a contractor's profit percentage actually falls as costs rise (since fee stays flat against a growing cost base), which softens — though does not eliminate — the contractor's incentive to hold costs down.
— INFERRED
Categorical CAS and audit exemption for firm-fixed-price and commercial-item contracts — Because the government has no cost-reimbursement exposure on FFP or commercial contracts, it forgoes both certified cost-or-pricing data requirements and CAS coverage on those awards, trading audit visibility for reliance on market price competition as the cost-discipline mechanism.
✓ DOCUMENTED