What does a COR actually do on my contract, and how is that different from the contracting officer?

The Contracting Officer's Representative (COR) is the technical expert who monitors your performance, while the Contracting officer (CO or KO) holds the authority to modify the contract. The CO is the only person who can legally change the contract terms, conditions, price, or scope of work. Your COR helps the CO administer the contract, but they do not have the authority to bind the government contractually. This means if a COR or a facility manager tells you to do something outside the contract's scope, you must elevate that request to the CO for a contract modification. Otherwise, you risk performing work for which you will not be paid.

The CO is ultimately responsible for your Contractor Performance Assessment Reporting System (CPARS) rating. The COR provides input to the CO, but the final evaluation is the CO's responsibility. It is important to communicate clearly and consistently with both your COR and the CO. If you receive conflicting instructions, always refer back to the contract and seek clarification from the CO.

The contracting officer is the only person who can change your contract. FAR 1.602-1 gives the CO exclusive authority to enter into, administer, and terminate contracts. FAR 43.102 says only contracting officers acting within the scope of their authority may execute contract modifications.

A Contracting Officer's Representative (COR) assists with technical monitoring or administration under FAR 1.604. FAR 1.602-2(d) requires the CO to designate the COR in writing, with copies to the contractor, and to spell out the COR's authority and limits. FAR 1.602-2(d)(5) is blunt: the COR has no authority to make any commitments or changes that affect price, quality, quantity, delivery, or other terms and conditions, and may not direct you to operate outside the contract.

On our federal building guard contract, the facility manager is a customer, not a contracting official. When the COR or the facility manager asks for work outside the statement of work, we stop and email the CO with the appointment letter and the SOW cite. Doing the extra work without a mod is an unauthorized commitment risk and unpaid work.

On CPARS, FAR 42.1503(a)(1)(ii) lets agency procedures assign evaluation roles to contracting officers, CORs, project managers, and program managers. FAR 42.1503(a)(2) says if agency procedures do not name who owns the evaluation, the contracting officer is responsible. Ask the CO in writing who the Assessing Official is on your contract, and keep your performance evidence tied to that person.