Contract Line Item Number (CLIN)
A Contract Line Item Number (CLIN) identifies a separately priced deliverable in a federal contract. FAR subpart 4.10 requires each line item to carry a single unit price, its own delivery schedule, and one accounting classification; DoD numbers them 0001 through 9999.
Line items are the contract's basic unit of structure. Under FAR 4.1003, each separately identifiable deliverable gets its own line with a single unit price or total price, one accounting classification citation, its own delivery schedule or period of performance, and a single pricing arrangement. Subline items (SLINs) break a CLIN down further — deliverable SLINs for related variants, informational SLINs for tracking assemblies or funding (FAR 4.1004).
DoD layers its uniform numbering system on top: four numeric digits from 0001 through 9999, informational SLINs numbered 01 through 99, separately identified SLINs lettered AA through ZZ with I and O excluded (DFARS PGI 204.7103-2 and 204.7104). Exhibits, including CDRLs, carry letter identifiers.
Bad CLIN structure stays invisible until invoicing. Mixed appropriations on one line, options that payment systems cannot parse, or services lumped with hardware all turn into modification work the original drafter never budgeted.
Regulatory Reference
FAR Subpart 4.10; DFARS Subpart 204.71; DFARS PGI 204.7103-2
RFO Status
The FAR Overhaul model deviation moves line-item policy from subpart 4.10 to section 4.202, and Part 4 is in the June 2026 proposed rule covering Parts 1, 2, 4, 33, 39, 40, and 53; DoD's DFARS numbering scheme is unchanged.
Category
Documents & Artifacts
How AcqBot Helps
AcqBot builds the CLIN structure from your requirement data: it splits deliverables that need separate lines, flags mixed funding or pricing arrangements on a single line, and applies DoD numbering rules for SLINs and exhibits before the document reaches your contract writing system.
Related glossary entries
Justification & Approval (J&A)
A Justification & Approval (J&A) is the formal document required by FAR 6.303 to justify awarding a federal contract without full and open competition, citing one of seven statutory exceptions and approved at thresholds based on dollar value.
Performance Work Statement (PWS)
A Performance Work Statement (PWS) describes required outcomes and measurable performance standards for a services acquisition rather than prescribing how the work must be done, enabling contractors to propose their own methods under performance-based acquisition.
Statement of Work (SOW)
A Statement of Work (SOW) is the contract document that prescribes, in specific and directive terms, the tasks a contractor must perform, the deliverables due, and the schedule — placing responsibility for the approach on the government.
Statement of Objectives (SOO)
A Statement of Objectives (SOO) is a brief government document stating top-level acquisition objectives and desired outcomes, leaving offerors free to propose their own technical approach and performance work statement in response.