48 CFR 232.703-1: 232.703-1 General.

(1) A fixed-price contract may be incrementally funded only if—

(i) The contract (excluding any options) or any exercised option—

(A) Is for severable services;

(B) Does not exceed one year in length; and

(C) Is incrementally funded using funds available (unexpired) as of the date the funds are obligated; or

(ii) The contract uses funds available from multiple (two or more) fiscal years and—

(A) The contract is funded with research and development appropriations; or

(B) Congress has otherwise authorized incremental funding.

(2) An incrementally funded fixed-price contract shall be fully funded as soon as funds are available.