48 CFR § 43.103 - 43.103 Types of contract modifications.

---
identifier: "/us/cfr/t48/s43.103"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "48 CFR § 43.103 - 43.103   Types of contract modifications."
title_number: 48
title_name: "Federal Acquisition Regulations System"
section_number: "43.103"
section_name: "43.103   Types of contract modifications."
chapter_number: 1
chapter_name: "FEDERAL ACQUISITION REGULATION"
subchapter_number: "G"
subchapter_name: "CONTRACT MANAGEMENT"
part_number: "43"
part_name: "CONTRACT MODIFICATIONS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "41 U.S.C. 1121(b); 40 U.S.C. 121(c); 10 U.S.C. chapter 4 and 10 U.S.C. chapter 137 legacy provisions (see 10 U.S.C. 3016); and 51 U.S.C. 20113."
regulatory_source: "48 FR 42386, Sept. 19, 1983, unless otherwise noted."
cfr_part: "43"
---


# 43.103 43.103   Types of contract modifications.

Contract modifications are of the following types:

(a) *Bilateral.* A bilateral modification (supplemental agreement) is a contract modification that is signed by the contractor and the contracting officer. Bilateral modifications are used to—

(1) Make negotiated equitable adjustments resulting from the issuance of a change order;

(2) Definitize letter contracts; and

(3) Reflect other agreements of the parties modifying the terms of contracts.

(b) *Unilateral.* A unilateral modification is a contract modification that is signed only by the contracting officer. Unilateral modifications are used, for example, to—

(1) Make administrative changes;

(2) Issue change orders;

(3) Make changes authorized by clauses other than a changes clause (*e.g.,* Property clause, Options clause, or Suspension of Work clause); and

(4) Issue termination notices.

[48 FR 42386, Sept. 19, 1983, as amended at 66 FR 2133, Jan. 10, 2001]