Indefinite Delivery / Indefinite Quantity Contract (IDIQ)
A federal contract type that pre-qualifies vendors and pre-negotiates terms, letting agencies place multiple orders against the contract without re-competing.
Definition
An IDIQ contract (FAR Subpart 16.5) does not commit the agency to a specific quantity. Instead, the agency awards an IDIQ to one or more vendors with pricing, terms, and a contract ceiling in place. The agency then issues task orders (for services) or delivery orders (for products) as needs arise, drawing against the IDIQ contract. IDIQs can be single-award or multiple-award; multiple-award IDIQs have a pool of vendors who compete for each task order.
When it applies
Used when the agency anticipates ongoing needs but cannot predict quantity or timing. Common in federal IT, professional services, defense engineering, and base operations. Winning an IDIQ slot is often a multi-year revenue commitment but requires significant up-front bid investment. Many of the largest federal contracts (GSA Schedule, OASIS, GWACs) are structured as IDIQs.