4.6 Time-and-Materials, Labor-Hour & Letter Contracts (FAR Subpart 16.6)

4.6 Time-and-Materials, Labor-Hour & Letter Contracts (FAR Subpart 16.6)

FAR Subpart 16.6 prescribes policies and procedures for special contracting methods, including Time-and-Materials (T&M), Labor-Hour (LH), and Letter Contracts. These instruments are classified as high-risk contract types because they lack firm initial pricing or firm scope commitments, requiring stringent government controls and administrative safeguards.

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1. Time-and-Materials (T&M) & Labor-Hour (LH) Contracts (FAR 16.601 & 16.602)

A Time-and-Materials contract provides for acquiring supplies or services on the basis of:

1. Direct Labor Hours: Billed at specified fixed hourly rates that include direct labor wages, indirect overhead, general and administrative (G&A) expenses, and profit; and
2. Materials: Reimbursed at actual cost (plus allowable material handling costs, such as G&A, to the extent supported by contractor accounting practices).

Labor-Hour Variant (FAR 16.602): A Labor-Hour contract is identical to a T&M contract except that materials are not supplied or billed by the contractor.

Mandatory Statutory Conditions for Use (FAR 16.601(c))

A T&M or LH contract may be used ONLY WHEN the contracting officer determines that no other contract type is suitable because it is impossible at the time of contract award to estimate the extent or duration of work or to estimate costs with any reasonable degree of confidence.

Mandatory Determination & Findings (D&F) (FAR 16.601(d))

Before issuing a T&M or LH solicitation, the contracting officer must execute a formal written Determination and Findings (D&F) establishing that:

• No other contract type is suitable;
• Government surveillance will be conducted to ensure efficient performance;
• For commercial items (FAR 12.207), a special D&F approved by the Head of Contracting Activity (HCA) is required establishing extensive market research.

Binding Ceiling Price Requirement (FAR 16.601(d)(2))

Each T&M and LH contract MUST establish a ceiling price that the contractor exceeds at its own risk. The contracting officer may not increase the ceiling price without executing a formal D&F demonstrating that the modification is in the government's best interest.

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2. Letter Contracts & Undefinitized Contract Actions (UCAs) (FAR 16.603)

A Letter Contract is a written preliminary contractual instrument that authorizes the contractor to begin manufacturing supplies or performing services immediately before negotiating a definitive contract.

Strict Authorization Standard (FAR 16.603-2)

Letter contracts are authorized ONLY WHEN the government's interest requires an immediate commitment and negotiating a definitive contract in time to meet the requirement is impossible. Letter contracts must be approved in writing by the Head of Contracting Activity (HCA).

Mandatory Definitization Schedule (FAR 16.603-2(c))

To prevent letter contracts from lingering as unpriced open commitments, FAR 16.603 mandates a rigid Definitization Schedule:

$\text{Definitization Deadline} = \text{Within } \mathbf{180 \text{ days}} \text{ after award OR before } \mathbf{50\%} \text{ of work is completed (Whichever occurs first)}$

Maximum Government Funding Obligation Ceiling (FAR 16.603-2(d))

Prior to definitization, the government's financial liability and funding obligation is strictly restricted to prevent contractor cost inflation:

$\text{Maximum Pre-Definitization Obligation} = \mathbf{50\%} \text{ of Total Estimated Maximum Cost}$

Exception: The maximum obligation limit may be increased up to 75% of estimated cost in extraordinary, high-urgency circumstances upon written approval of the ratifying official.

Profit Assessment during Definitization (FAR 15.404-4(c)(4)(ii))

During definitization negotiations, the contracting officer must evaluate the contractor's profit/fee rate taking into account that the contractor bore reduced cost risk during the initial unpriced performance period prior to definitization.

Detailed Determination & Findings (D&F) Requirements for T&M Contracts

Because Time-and-Materials (T&M) and Labor-Hour (LH) contracts shift significant cost risk to the Government, FAR 16.601(d) mandates that the Contracting Officer execute a comprehensive written Determination and Findings (D&F) prior to issuing a T&M solicitation. The D&F must establish that no other contract type is suitable because the scope, extent, or duration of work cannot be estimated with sufficient confidence to use a fixed-price contract. Furthermore, for commercial T&M acquisitions under FAR 12.207, the D&F must be approved by the Head of the Contracting Activity (HCA) and include a detailed market research report proving that commercial fixed-price alternatives were thoroughly evaluated and rejected.

Loaded Hourly Rate Components & Audit Oversight

The fixed hourly labor rates negotiated in T&M and LH contracts are loaded rates that incorporate four distinct cost components: direct labor wages paid to employees, fringe benefits (such as health insurance and retirement), indirect overhead and General & Administrative (G&A) expenses, and profit. While the labor rates remain fixed, the Government reimburses the actual number of hours worked, up to the ceiling price. To protect against over-billing, Contracting Officers and CORs must verify that workers assigned to T&M contracts satisfy the exact educational and experience qualifications specified for each labor category in the contract schedule.

Undefinitized Contract Action (UCA) Profit Adjustments

When definitizing a Letter Contract or Undefinitized Contract Action (UCA), the Contracting Officer must apply a specialized profit evaluation under FAR 15.404-4(c)(4)(ii). Because the contractor performs a portion of the work under an unpriced letter contract before final price agreement is reached, the contractor bears significantly reduced cost risk during the pre-definitization period. Consequently, the Contracting Officer must reduce the profit or fee objective assigned to incurred pre-definitization costs to reflect the lower risk borne by the contractor during that period.