FAR and DFARS › FAR Part 43: Contract Modifications › Subpart 43.2
FAR 43.205 Contract clauses.
The codified text (eCFR, as of 2026-10-02). Under the Revolutionary FAR Overhaul ↗, agencies follow class deviations with new text for many parts while the formal rules go through the Federal Register: check the solicitation and your contract's clauses, which rule.
In plain English
This section tells contracting officers which Changes clauses to put in solicitations and contracts, depending on the contract type (fixed-price, cost-reimbursement, time-and-materials or labor-hour) and what is being bought (supplies, services, construction, research and development, and similar categories). It matters to contractors because the Changes clause in your contract controls how the government can order changes and which version of that clause applies to your work.
Applies to: Contracting officers choosing Changes clauses for solicitations and contracts
Key terms: Changes—Fixed-Price · Changes—Cost-Reimbursement · Changes—Time-and-Materials or Labor-Hours · Changes · Changes and Changed Conditions
Written by AI from this section's text. A guide, not legal advice: the text below rules.
The text
(a)(1) The contracting officer shall insert the clause at 52.243-1, Changes—Fixed-Price, in solicitations and contracts when a fixed-price contract for supplies is contemplated.
(2) If the requirement is for services, other than architect-engineer or other professional services, and no supplies are to be furnished, the contracting officer shall use the clause with its Alternate I.
(3) If the requirement is for services (other than architect-engineer services, transportation, or research and development) and supplies are to be furnished, the contracting officer shall use the clause with its Alternate II.
(4) If the requirement is for architect-engineer or other professional services, the contracting officer shall use the clause with its Alternate III.
(5) If the requirement is for transportation services, the contracting officer shall use the clause with its Alternate IV.
(6) If it is desired to include the clause in solicitations and contracts when a research and development contract is contemplated, the contracting officer shall use the clause with its Alternate V.
(b)(1) The contracting officer shall insert the clause at 52.243-2, Changes—Cost-Reimbursement, in solicitations and contracts when a cost-reimbursement contract for supplies is contemplated.
(2) If the requirement is for services and no supplies are to be furnished, the contracting officer shall use the clause with its Alternate I.
(3) If the requirement is for services and supplies are to be furnished, the contracting officer shall use the clause with its Alternate II.
(4) If the requirement is for construction, the contracting officer shall use the clause with its Alternate III.
(5) [Reserved]
(6) If it is desired to include the clause in solicitations and contracts when a research and development contract is contemplated, the contracting officer shall use the clause with its Alternate V.
(c) Insert the clause at 52.243-3, Changes—Time-and-Materials or Labor-Hours, in solicitations and contracts when a time-and-materials or labor-hour contract is contemplated. The contracting officer may vary the 30-day period in paragraph (c) of the clause according to agency procedures.
(d) The contracting officer shall insert the clause at 52.243-4, Changes, in solicitations and contracts for (1) dismantling, demolition, or removal of improvements; and (2) construction, when a fixed-price contract is contemplated and the contract amount is expected to exceed the simplified acquisition threshold.
(e) The contracting officer shall insert the clause at 52.243-5, Changes and Changed Conditions, in solicitations and contracts for construction, when the contract amount is not expected to exceed the simplified acquisition threshold.
(f) The contracting officer may insert a clause, substantially the same as the clause at 52.243-6, Change Order Accounting, in solicitations and contracts for supply and research and development contracts of significant technical complexity, if numerous changes are anticipated. The clause may be included in solicitations and contracts for construction if deemed appropriate by the contracting officer.
Sections it refers to
← 43.204 Administration. · 43.301 Use of forms. →
Rule changes for FAR Part 43
- Federal Acquisition Regulation; Technical Amendments ↗ · final rule 2025-08-07 · effective 2025-08-07
Source: eCFR, 48 CFR chapters 1 and 2 (GPO GovInfo bulk data) ↗. Plain words for the terms: glossary.