Federal Contracting Glossary
Contract Line Item (CLIN)
A separately identified, priced item of work in a federal contract, used to organize deliverables, funding, and pricing.
Definition
A Contract Line Item Number (CLIN) is a separately identified element of supplies or services in a federal contract, each with its own description, quantity, unit price, and delivery or performance terms. CLINs (and their sub-line items, SLINs) let the government structure a contract into discrete, individually priced pieces — for example separating base-year services from option years, or splitting deliverables that are funded from different appropriations.
CLIN structure matters for both pricing and administration. A solicitation's pricing schedule tells offerors exactly how to price each CLIN, and evaluators total the priced CLINs (including options) to compare offers. Misreading the CLIN structure — pricing the wrong unit or omitting an option CLIN — is a common, avoidable proposal error.
How this affects your proposal
Price every CLIN exactly as the pricing schedule directs, including all option CLINs the evaluation will total. Read the CLIN structure carefully: units, quantities, and whether items are fixed-price or cost-reimbursable can differ line by line.
Common questions about contract line item (clin)
What is the difference between a CLIN and a SLIN?
A CLIN is a top-level line item; a SLIN (sub-line item) breaks a CLIN into finer pieces — for example to track different accounting classifications or delivery points — without changing the overall scope of that CLIN.
Are option CLINs included in the price evaluation?
Usually yes — agencies commonly evaluate the total of base and all option CLINs, even though options are exercised at the government's discretion. Check Section M for exactly which CLINs are evaluated.
Related terms
IDIQ Contract
An Indefinite-Delivery, Indefinite-Quantity contract that lets an agency place task or …
Full and Open Competition
A federal procurement open to all responsible sources, where any interested offeror may…
Set-Aside
A procurement reserved for a defined category of small business — limiting competition …
Writing a proposal that involves contract line item (clin)?
GovCon is the AI proposal-writing tool built specifically for federal offerors. Free plan, no card required.
Start free →See all federal contracting terms in the GovCon glossary, or read our long-form federal contracting guides.