CPFF vs CPIF Contracts: Cost-Plus Comparison

Cost-Plus-Fixed-Fee (CPFF)

Under a CPFF contract (FAR 16.306), the government reimburses the contractor for all allowable, allocable, and reasonable costs incurred during performance, plus a fixed dollar amount of fee. The fee does not vary with actual costs. If the estimated cost is $10 million and the fixed fee is $800,000, the contractor earns $800,000 regardless of whether actual costs come in at $8 million or $12 million.

CPFF contracts come in two forms: completion and term. A completion form requires the contractor to deliver a defined end product (a report, prototype, or system). The fixed fee is earned upon delivery. A term form requires the contractor to provide a specified level of effort over a defined period. The fee is earned by performing the level of effort, regardless of whether the work results in a deliverable.

CPFF is the most common cost-reimbursement contract type because it is straightforward to administer. The fee is negotiated at award and does not change, eliminating disputes over fee calculations during performance. However, the contractor has limited financial incentive to reduce costs because the fee is fixed regardless of cost performance.

Cost-Plus-Incentive-Fee (CPIF)

A CPIF contract (FAR 16.304) reimburses allowable costs and provides a fee that adjusts based on cost performance relative to a negotiated target cost. The contract establishes a target cost, a target fee, a minimum fee, a maximum fee, and a fee adjustment formula (sharing ratio).

For example, consider a CPIF contract with a $10M target cost, $900K target fee, $400K minimum fee, $1.4M maximum fee, and an 80/20 sharing ratio (government/contractor). If the contractor delivers the work for $9M — $1M under the target — the fee increases by 20% of the savings: $900K + ($1M x 0.20) = $1.1M. If costs overrun to $11M, the fee decreases: $900K - ($1M x 0.20) = $700K. The fee cannot go below $400K or above $1.4M.

This structure creates a financial incentive for the contractor to control costs. Unlike CPFF, where the contractor earns the same fee regardless of cost efficiency, CPIF rewards cost savings and penalizes overruns. The sharing ratio determines the strength of the incentive — a 50/50 split provides stronger contractor motivation than 90/10.

Fee Structures and Calculations

Risk Allocation Differences

Both CPFF and CPIF place the majority of cost risk on the government, since both reimburse actual costs. However, CPIF introduces a degree of shared cost risk through the fee adjustment mechanism. The contractor's financial exposure under CPIF is limited to the difference between the target fee and the minimum fee — a much smaller risk than under FFP contracts where the entire cost overrun is the contractor's loss.

From the government's perspective, CPIF provides better value because it motivates the contractor to find efficiencies. If the contractor can perform the work below the target cost, the government shares in those savings through the sharing ratio (the government's share of savings typically ranges from 60% to 90%). This makes CPIF particularly attractive for programs where cost growth has been a historical problem.

For contractors, the choice between CPFF and CPIF involves assessing your confidence in cost estimation. If you are confident in your cost estimates and believe you can perform below target, CPIF offers upside potential. If the work is highly uncertain and cost estimation is unreliable, CPFF provides fee certainty regardless of how costs evolve.

When Each Contract Type Is Used

CPFF Is Preferred When:

• The work involves basic research or exploratory development with high uncertainty
• Cost estimation is impractical because the scope cannot be well-defined in advance
• The government wants simplicity in contract administration
• Level-of-effort contracts where a defined deliverable is not the primary output

CPIF Is Preferred When:

• The work is complex but sufficiently defined to establish meaningful cost targets
• The government wants to incentivize cost control on large programs
• Historical cost data exists to set realistic target costs and sharing ratios
• Major defense systems development, advanced technology programs, or large-scale services

In practice, CPFF is far more common than CPIF. CPIF requires more sophisticated cost estimation, negotiation of sharing ratios and fee boundaries, and ongoing fee calculation during performance. Many agencies default to CPFF for simplicity, even when CPIF might provide better value.

DCAA Audit Implications

Both CPFF and CPIF contracts require a DCAA-adequate accounting system and are subject to incurred cost audits. The contractor must track actual costs by contract, maintain adequate indirect rate pools, and submit annual incurred cost proposals. These audit requirements are identical for both contract types.

The difference lies in fee auditing. For CPFF, the fee is established at award and does not change, so there is no fee calculation to audit. For CPIF, the final fee must be calculated based on actual versus target costs, which requires auditing the cost performance data and applying the sharing formula. This adds an additional step to contract closeout.

Both contract types require compliance with FAR Part 31 (Cost Principles) for determining allowable costs, and contracts over $7.5 million require compliance with Cost Accounting Standards (CAS). The accounting infrastructure required is the same — the CPIF fee adjustment simply adds one more calculation layer on top of the standard cost-type audit process.