Inaugural Committee Transparency Act of 2018 This bill requires the presidential inaugural committee to disclose to the Federal Election Commission, by 90 days after the presidential inaugural ceremony, any disbursement made in an amount equal to or greater than $200 and the purpose of each disbursement. The committee must also disclose the name and address of the person to whom the disbursement was made, the date of the disbursement, and the total amount and purpose of the disbursement. The committee must disburse any remaining donated funds not later than 90 days after the inaugural ceremony, but may request an extension of such 90-day period.