Bridge Contract Transparency and Accountability Act of 2018 This bill directs the Office of Federal Procurement Policy to submit reports to Congress on the policies, practices, and uses of bridge contracts across the federal government. (A bridge contract is generally an extension to an existing contract or a new short-term contract awarded to an incumbent contractor to avoid a lapse in service caused by a delay in awarding a follow-on contract.) The Federal Acquisition Regulatory Council shall amend the Federal Acquisition Regulation to provide for: (1) a common definition of bridge contracts, and (2) the appropriate use of such contracts. Federal agencies must develop policies and procedures that seek to minimize the use of bridge contracts.