2 CFR 200.110 – Effective/applicability date
(a) The standards set forth in this part that affect the administration of Federal awards issued by Federal awarding agencies become effective once implemented by Federal awarding agencies or when any future amendment to this part becomes final.
(b) Existing negotiated indirect cost rates (as of the publication date of the revisions to the guidance) will remain in place until they expire. The effective date of changes to indirect cost rates must be based upon the date that a newly re-negotiated rate goes into effect for a specific non-Federal entity’s fiscal year. Therefore, for indirect cost rates and cost allocation plans, the revised Uniform Guidance (as of the publication date for revisions to the guidance) become effective in generating proposals and negotiating a new rate (when the rate is re-negotiated).