In a more traditional environment, Congress might signal its support for school vouchers by authorizing and appropriating funds for a grant program that allocates funds for such purposes. Instead, Congress used the recently enacted reconciliation bill (H.R. 1; One Big Beautiful Bill Act [OBBBA]) to create a federal tax credit that supports the same objective through the tax code.
The Congressional Budget Office (CBO) estimates that the new credit will reduce federal revenues by $26 billion over 10 years, making it roughly comparable to a grant program funded at $2.6 billion per year. Moreover, there is no cap on the credit, so it could cost more or less, depending on state uptake.