Congressional Budget Office Cost Estimate: S. 34: Midnight Rules Relief Act of 2017 [open pdf - 14KB]
"S. 34 would amend the Congressional Review Act (CRA) to allow en bloc disapproval of multiple regulations issued during a President's final year in office. Under the CRA, the Congress can only disapprove one regulation at a time. Although the bill could affect how the Congress uses the CRA and thus affect which regulations are disapproved, enacting the bill would have no effect on the budget. Regulations can affect the cost of entitlement programs as well as the collection of fees, and changes to those regulations could either increase or decrease federal spending or revenues. However, any budgetary effects would result from future legislation that disapproved the regulations. Enacting the legislation would not affect direct spending and revenues; therefore, pay-as-you-go procedures apply. CBO [Congressional Budget Office] estimates that enacting S. 34 would not increase net direct spending or on-budget deficits in any of the four consecutive 10-year periods beginning in 2028."
Congressional Budget Office: https://www.cbo.gov