FAR 16.504—Indefinite-quantity contracts.
Plain-English Summary
FAR 16.504 explains how indefinite-quantity (IDIQ) contracts work and when contracting officers should use them. It covers the basic structure of an IDIQ contract, including the Government’s obligation to order a stated minimum, the contractor’s obligation to furnish quantities up to a stated maximum, and how minimum and maximum quantities may be expressed in units or dollars. It also addresses how to set reasonable minimum and maximum quantities, what must be included in the solicitation and contract (period of performance, options, scope description, ordering procedures, authorized ordering activities, and oral-order authority), and when an IDIQ is appropriate based on recurring needs and uncertainty in exact quantities. The section further establishes a strong preference for multiple-award IDIQ contracts, explains the acquisition-planning factors and exceptions for using multiple awards, requires documentation of the decision, and imposes special approval requirements for certain large single-award task or delivery order contracts over $150 million. In practice, this section is about preserving flexibility for the Government while keeping the contract legally binding, competition-focused, and properly structured so orders can be placed efficiently without exceeding the contract’s scope or statutory limits.
Key Rules
Minimum and maximum quantities
An IDIQ contract must state a minimum quantity the Government is obligated to order and a maximum quantity the contractor may be required to furnish. The minimum must be more than nominal, and the maximum should be based on a rational estimate such as market research, historical trends, or user surveys.
Fixed period and options
The solicitation and contract must specify the contract period, including the number of options and the period covered by each option. This ensures the ordering window is clear and prevents the Government from using the contract outside its stated term.
Scope must be reasonably described
The contract must include a statement of work, specifications, or other description that reasonably defines the general scope, nature, complexity, and purpose of the supplies or services. The description must be detailed enough for offerors to decide whether to compete and to keep later orders within scope.
Ordering procedures required
The contract must state how orders will be issued, including the ordering media, and, for multiple-award contracts, the fair-opportunity procedures and selection criteria under FAR 16.505(b)(1). It must also identify which activities are authorized to place orders.
Oral orders only if controlled
Oral orders may be authorized only if the Government has procedures for obligating funds and the oral orders are confirmed in writing. This protects against unauthorized commitments and disputes over what was ordered.
Use only for recurring uncertain needs
Contracting officers should use an IDIQ contract only when the Government cannot predetermine quantities above a minimum and when a recurring need is anticipated. It is not the right vehicle for one-time or highly predictable requirements.
Multiple-award preference
Except for advisory and assistance services, the contracting officer must, to the maximum extent practicable, prefer multiple awards under a single solicitation for the same or similar supplies or services. The goal is to preserve competition for future orders.
Multiple-award decision factors and limits
The contracting officer must consider scope, complexity, order frequency, resource mix, and the ability to maintain competition. Multiple awards should not be used when only one source can meet the need, a single award would provide better terms, administration costs outweigh benefits, the work is too integrated for multiple contractors, the estimated value is at or below the simplified acquisition threshold, or multiple awards are otherwise not in the Government’s best interest.
Document the award approach
The decision to use or not use multiple awards must be documented in the acquisition plan or contract file. Agencies may also determine that a class of acquisitions is not suitable for multiple awards.
Special approval for large single-source awards
No task or delivery order contract estimated to exceed $150 million, including options, may be awarded to a single source unless the head of the agency makes a written determination that one of the specified exceptions applies. These exceptions include integrated work requiring one source, certain firm-fixed-price structures with established prices, or only one qualified source at a reasonable price.
Responsibilities
Contracting Officer
Determine whether an IDIQ is appropriate, set a realistic minimum and maximum, define the contract period and scope, establish ordering procedures and authorized ordering activities, decide whether multiple awards should be used, document that decision, and ensure any oral-order authority is supported by fund-obligation and written-confirmation procedures.
Contracting Officer
For multiple-award IDIQs, plan for fair opportunity among awardees, avoid structuring awards so that one contractor effectively becomes sole source for portions of the work, and select the number of awards based on scope, complexity, expected order patterns, resource needs, and competition maintenance.
Head of the Agency
Approve in writing any single-source task or delivery order contract over $150 million when required by the regulation, and support the required exception finding.
Agency/Acquisition Planning Team
Assess whether multiple awards are appropriate during acquisition planning, consider market conditions and administration burden, and ensure the acquisition plan or contract file reflects the rationale for the chosen contract structure.
Contractor
Be prepared to furnish the stated minimum if ordered and to perform additional ordered quantities up to the contract maximum, while complying with the ordering procedures and any order-specific limits stated in the contract.
Ordering Activities/Authorized Users
Place orders only if authorized by the contract, follow the stated ordering media and procedures, and confirm oral orders in writing when oral ordering is permitted.
Practical Implications
IDIQ contracts are useful when demand is real but uncertain, but they must be carefully sized; a minimum that is too low can make the contract vulnerable, while a maximum that is too high can distort competition and pricing.
The scope statement is critical because every later order must fit within it; vague or overly broad descriptions can lead to scope disputes, protests, or improper ordering.
Multiple-award IDIQs are the default preference, so contracting officers should expect to justify a single-award approach with market facts, workload structure, or administrative considerations.
Fair-opportunity procedures matter operationally because they govern how task and delivery orders are competed among awardees; weak procedures can undermine competition and create protest risk.
Large single-source task or delivery order contracts face heightened scrutiny, so agencies should identify early whether the $150 million threshold may be exceeded and whether a written head-of-agency determination will be needed.
Official Regulatory Text
(a) Description . An indefinite-quantity contract provides for an indefinite quantity, within stated limits, of supplies or services during a fixed period. The Government places orders for individual requirements. Quantity limits may be stated as number of units or as dollar values. (1) The contract must require the Government to order and the contractor to furnish at least a stated minimum quantity of supplies or services. In addition, if ordered, the contractor must furnish any additional quantities, not to exceed the stated maximum. The contracting officer should establish a reasonable maximum quantity based on market research, trends on recent contracts for similar supplies or services, survey of potential users, or any other rational basis. (2) To ensure that the contract is binding, the minimum quantity must be more than a nominal quantity, but it should not exceed the amount that the Government is fairly certain to order. (3) The contract may also specify maximum or minimum quantities that the Government may order under each task or delivery order and the maximum that it may order during a specific period of time. (4) A solicitation and contract for an indefinite quantity must- (i) Specify the period of the contract, including the number of options and the period for which the Government may extend the contract under each option; (ii) Specify the total minimum and maximum quantity of supplies or services the Government will acquire under the contract; (iii) Include a statement of work, specifications, or other description, that reasonably describes the general scope, nature, complexity, and purpose of the supplies or services the Government will acquire under the contract in a manner that will enable a prospective offeror to decide whether to submit an offer; (iv) State the procedures that the Government will use in issuing orders, including the ordering media, and, if multiple awards may be made, state the procedures and selection criteria that the Government will use to provide awardees a fair opportunity to be considered for each order (see 16.505 (b)(1)); (v) Include a description of the activities authorized to issue orders; and (vi) Include authorization for placing oral orders, if appropriate, provided that the Government has established procedures for obligating funds and that oral orders are confirmed in writing. (b) Application . Contracting officers may use an indefinite-quantity contract when the Government cannot predetermine, above a specified minimum, the precise quantities of supplies or services that the Government will require during the contract period, and it is inadvisable for the Government to commit itself for more than a minimum quantity. The contracting officer should use an indefinite-quantity contract only when a recurring need is anticipated. (c) Multiple award preference- (1) Planning the acquisition. (i) Except for indefinite-quantity contracts for advisory and assistance services as provided in paragraph (c)(2) of this section, the contracting officer must, to the maximum extent practicable, give preference to making multiple awards of indefinite-quantity contracts under a single solicitation for the same or similar supplies or services to two or more sources. (ii) (A) The contracting officer must determine whether multiple awards are appropriate as part of acquisition planning. The contracting officer must avoid situations in which awardees specialize exclusively in one or a few areas within the statement of work, thus creating the likelihood that orders in those areas will be awarded on a sole-source basis; however, each awardee need not be capable of performing every requirement as well as any other awardee under the contracts. The contracting officer should consider the following when determining the number of contracts to be awarded: (1) The scope and complexity of the contract requirement. (2) The expected duration and frequency of task or delivery orders. (3) The mix of resources a contractor must have to perform expected task or delivery order requirements. (4) The ability to maintain competition among the awardees throughout the contracts’ period of performance. (B) The contracting officer must not use the multiple award approach if- (1) Only one contractor is capable of providing performance at the level of quality required because the supplies or services are unique or highly specialized; (2) Based on the contracting officer’s knowledge of the market, more favorable terms and conditions, including pricing, will be provided if a single award is made; (3) The expected cost of administration of multiple contracts outweighs the expected benefits of making multiple awards; (4) The projected task orders are so integrally related that only a single contractor can reasonably perform the work; (5) The total estimated value of the contract is at or below the simplified acquisition threshold; or (6) Multiple awards would not be in the best interests of the Government. (C) The contracting officer must document the decision whether or not to use multiple awards in the acquisition plan or contract file. The contracting officer may determine that a class of acquisitions is not appropriate for multiple awards (see subpart 1.7 ). (D) (1) No task or delivery order contract in an amount estimated to exceed $150 million (including all options) may be awarded to a single source unless the head of the agency determines in writing that- (i) The task or delivery orders expected under the contract are so integrally related that only a single source can reasonably perform the work; (ii) The contract provides only for firm-fixed price (see 16.202 ) task or delivery orders for- ( A ) Products for which unit prices are established in the contract; or ( B ) Services for which prices are established in the contract for the specific tasks to be performed; (iii) Only one source is qualified and capable of performing the work at a reasonable price to the Government; or (iv) It is necessary in the public interest to award the contract to a single source due to exceptional circumstances. (2) The head of the agency must notify Congress within 30 days after any determination under paragraph (c)(1)(ii)(D)( 1 )( iv ) of this section. (3) The requirement for a determination for a single-award contract greater than $150 million- (i) Is in addition to any applicable requirements of subpart 6.3 ; and (ii) Is not applicable for architect-engineer services awarded pursuant to subpart 36.6 . (2) Contracts for advisory and assistance services. (i) Except as provided in paragraph (c)(2)(ii) of this section, if an indefinite-quantity contract for advisory and assistance services exceeds 3 years and $20 million, including all options, the contracting officer must make multiple awards unless- (A) The contracting officer or other official designated by the head of the agency determines in writing, as part of acquisition planning, that multiple awards are not practicable. The contracting officer or other official must determine that only one contractor can reasonably perform the work because either the scope of work is unique or highly specialized or the tasks so integrally related; (B) The contracting officer or other official designated by the head of the agency determines in writing, after the evaluation of offers, that only one offeror is capable of providing the services required at the level of quality required; or (C) Only one offer is received. (ii) The requirements of paragraph (c)(2)(i) of this section do not apply if the contracting officer or other official designated by the head of the agency determines that the advisory and assistance services are incidental and not a significant component of the contract.