41 CFR § 101-28.202-4
Reimbursement for services
June 9, 2020
Reimbursement for services rendered shall be made promptly after receipt of billing. The frequency for billing and reimbursement shall be established by the activity providing warehousing and storage services; however, billing and reimbursement shall be made not less frequently than quarterly nor more frequently than monthly.
[42 FR 2317, Jan. 11, 1977]