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Contract Modifications SOP

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This SOP has internal roles only.

This standard operating procedure (SOP) includes the following sections: Purpose, Procedure, Contacts, and Links.


To modify in writing a contract's terms or conditions, such as its statement of work, period of performance, quantity, or price.


Either the government or a contractor may propose to modify a contract. If a contractor requests a modification, its business office must submit a signed request to the contracting officer explaining the modification and its anticipated effect on the contract. Only contracting officers acting within their delegated authority may modify a contract or change a contractual commitment on behalf of the government.

There are two types of contract modifications: unilateral and bilateral.

  • Unilateral modifications are signed only by a contracting officer and are generally used to make administrative changes, issue change orders, make changes authorized by clauses other than the Changes clause, and issue termination notices.
  • Bilateral modifications (supplemental agreements) are signed by both the contracting officer and the contractor. Bilateral modifications can add new work or revise existing terms, and it may have cost implications.

Examples of contract modifications include:

  • A change order is a written order signed by the contracting officer, directing the contractor to make a change within the general scope of the contract that the Changes clause authorizes without the contractor’s consent. When change orders are not forward priced, they require two documents: the change order and a supplemental agreement reflecting the resulting equitable adjustment in contract terms. If an equitable adjustment in the contract price or delivery terms or both can be agreed upon in advance, only a supplemental agreement need be issued. See FAR Subpart 43.2, Change Orders for more information.
  • A modification adding new work outside the scope of the contract requires a justification for other than full and open competition (JOFOC) and results in a bilateral modification. See also FAR Subpart 6.3, Other Than Full and Open Competition.
  • An extension modification extends the date for completing contract requirements. This extension can be a cost or no-cost extension. A contractor submits a written request or proposal identifying the extension's impact on a contract and its funding. Contract extensions are bilateral modifications.
  • A cost overrun modification is necessary when the cost of performing a cost-reimbursement contract exceeds or is expected to exceed the total estimated cost in the contract. Here, a contractor needs additional funding to complete the requirements; no new work is performed. A cost overrun modification is bilateral.
  • A modification changing other terms of the contract, such as travel, subcontracts, equipment, key personnel, delivery, or schedule, can be initiated by either a contractor or the government. A contractor submits documentation requested by the contracting officer. These modifications are bilateral.
  • A modification making changes authorized by clauses other than the changes clause, such as property clause, options clause, incremental funding, or contracting officer's representative, is initiated by the government. These modifications may be executed as a unilateral modification, though a bilateral modification is recommended.
  • A modification making administrative changes that do not affect the rights of the parties, such as a change in the appropriation data or the paying office, is initiated by the government and may be executed as a unilateral modification.

Contracting Officer's Representatives

  • Initiate requests for changes to the work, funding, or period of performance by completing a Request for Change to Active Contract form and submitting it to the contracting officer.
  • Review proposals or cost estimates from contractors and provide technical and cost feedback to the contracting officer.
  • Participate in negotiations.
  • Recommend the modification to the contracting officer.
  • Provide the contracting officer with information he or she may request to finalize an action.

Note: Contracting Officer's Representatives are not authorized to issue or approve modifications, enter into agreements, or take any other action that changes a contract's cost or terms and conditions. Such "unauthorized commitments" are not binding for the government.

Contracting Officers

  • Request information from contractors, including a proposal, cost estimate, and supporting documentation submitted by the business office to the contracting officer.
  • Lead negotiations, when required.
  • Obtain funding approval, clearances, and determinations and findings, when necessary, and required reviews and approvals.
  • Issue modifications on SF-30, amendment of solicitation/modification of contract, and distribute to contractors within 10 working days after execution.


See the Office of Acquisitions staff listing for the appropriate contract specialist.

If you have knowledge to share or want more information on this topic, email with the title of this page or its URL and your question or comment. Thanks for helping us clarify and expand our knowledge base.


Acquisition Policy Memorandum

Lock icon: This link will not work for public visitors.Contracting Officer SOP

Lock icon: This link will not work for public visitors.Contracting Officer's Representative SOP

Lock icon: This link will not work for public visitors.Distribution of Contract Awards, Modifications, and Task Orders SOP

Lock icon: This link will not work for public visitors.Justification for Other than Full and Open Competition

FAR Subpart 1.602-3, Ratification of Unauthorized Commitments

FAR Subpart 4.2, Contract Distribution

FAR Part 43, Contract Modifications

FAR Subpart 52.243-7, Notification of Changes

HHSAR 301.602-3 Ratification of Unauthorized Commitments

HHSAR Subpart 306.3--Other than Full and Open Competition

HHSAR 342.7102 Contract modifications

Interim HHSAR changes related to the HHS JOFOC and LSJ templates

Last Updated June 23, 2015

Last Reviewed February 04, 2015