Federal Land Asset Inventory Reform Act of 2021 This bill directs the Department of the Interior to develop and maintain a current and accurate multipurpose cadastre (inventory) of federal real property (excluding Indian land) to support federal land management activities on federal real property, including resource development and conservation and agricultural use. Interior may enter cost-sharing agreements with states to include nonfederal real property in the cadastre. Interior shall report on (1) existing real property inventories or any components of any cadastre of federal real property, (2) consolidation of inventories and components, (3) the use of existing inventories and components of any cadastre, (4) cost savings that will be achieved, (5) a plan for implementation of this bill, and (6) recommendations for legislation. Interior shall (1) make the multipurpose cadastre publicly available on the internet, and (2) ensure that such cadastre includes the identification of all lands suitable for disposal pursuant to the Federal Land Policy and Management Act of 1976.