Tax Expenditures and Credits: Treasury's Role in Tax Incentives

The U.S. Department of the Treasury, through the Office of Tax Policy and in coordination with the Internal Revenue Service, shapes the design, cost estimation, and administration of tax expenditures — the collective term for deductions, exclusions, credits, deferrals, and preferential rates embedded in the federal tax code. These provisions redirect hundreds of billions of dollars annually away from general revenues toward targeted economic and social objectives. Understanding how Treasury structures and oversees these instruments clarifies why the federal tax system functions as both a revenue mechanism and a tool of active fiscal policy.

Definition and scope

A tax expenditure is a departure from the baseline structure of the federal income tax that reduces a taxpayer's liability in exchange for specific behavior, status, or investment. The Congressional Budget and Impoundment Control Act of 1974 (2 U.S.C. § 622(3)) formally defined tax expenditures as "revenue losses attributable to provisions of the Federal tax laws which allow a special exclusion, exemption, or deduction from gross income or which provide a special credit, a preferential rate of tax, or a deferral of tax liability."

Tax expenditures divide into two structurally distinct categories:

1. Tax deductions and exclusions — reduce the amount of income subject to tax, meaning their dollar value scales with the taxpayer's marginal rate. A $1,000 deduction is worth $220 to a taxpayer in the 22% bracket and $370 to one in the 37% bracket.
2. Tax credits — reduce tax liability dollar-for-dollar and therefore deliver the same nominal benefit regardless of the taxpayer's marginal rate. A $1,000 nonrefundable credit eliminates $1,000 of tax owed; a refundable credit can generate a payment even when no tax is owed.

The Office of Management and Budget publishes an annual Analytical Perspectives volume alongside the President's budget that catalogs estimated revenue losses from each tax expenditure provision (OMB Analytical Perspectives). The Joint Committee on Taxation independently produces companion estimates used by Congress (JCT Tax Expenditure Reports).

How it works

Treasury's Office of Tax Policy carries primary executive-branch responsibility for analyzing, drafting, and evaluating tax expenditure proposals. When Congress considers a new credit or incentive, Treasury analysts model the projected revenue cost using microsimulation models built on tax return data maintained by the IRS Statistics of Income division.

The administrative cycle for a tax incentive follows a structured sequence:

1. Legislative proposal — Treasury's Office of Tax Policy drafts or reviews proposed statutory language, ensuring compatibility with existing Internal Revenue Code provisions.
2. Revenue scoring — The Joint Committee on Taxation scores the proposal's 10-year budget impact before floor votes; Treasury may prepare parallel estimates for executive review.
3. Regulatory guidance — After enactment, Treasury issues regulations, notices, and revenue rulings through the Federal Register that define eligibility criteria, documentation requirements, and computational rules. These rules carry the force of law under 26 U.S.C. § 7805.
4. IRS administration — The Internal Revenue Service, operating as a Treasury bureau, processes claims, conducts audits, and enforces compliance with the enacted provision.
5. Annual reporting — Treasury reports estimated revenue losses in the Tax Expenditures section of the Analytical Perspectives volume, allowing Congress to compare the cost of each preference against direct spending alternatives.

The largest single tax expenditure in the federal budget is consistently the exclusion of employer-sponsored health insurance from taxable income, which the Joint Committee on Taxation estimated at approximately $316 billion in forgone revenue for fiscal year 2023 (JCT, "Estimates of Federal Tax Expenditures for Fiscal Years 2023–2027").

Common scenarios

Tax expenditures appear across the income tax code in forms that affect individual filers, corporations, and pass-through entities differently.

Individual tax credits — The Child Tax Credit, governed under 26 U.S.C. § 24, provides a per-child benefit that is partially refundable under the Additional Child Tax Credit rules, meaning low-income households can receive payments beyond their tax liability. The Earned Income Tax Credit, authorized under 26 U.S.C. § 32, is fully refundable and phases in with earned income before phasing out at higher income levels; the IRS estimated that 23 million eligible taxpayers claimed the EITC in tax year 2022 (IRS EITC Statistics).

Business investment incentives — The Research and Experimentation (R&E) credit under 26 U.S.C. § 41 subsidizes qualifying domestic research expenditures at a base rate of 20% of incremental qualified research expenses over a calculated base amount. Accelerated depreciation provisions, including bonus depreciation under 26 U.S.C. § 168(k), allow businesses to deduct a percentage of qualifying asset costs in the year of purchase rather than over the asset's useful life, representing a deferral rather than a permanent exclusion.

Energy and environmental credits — The Inflation Reduction Act of 2022 (Pub. L. 117-169) significantly expanded clean energy credits administered under Treasury and IRS oversight, including production credits for electricity generated from qualified renewable sources and investment credits for solar, wind, and battery storage installations. Treasury issued extensive guidance on these provisions through 2023 and 2024 to define "domestic content" requirements, transferability rules, and direct-pay options for tax-exempt entities.

Decision boundaries

Three distinctions clarify the boundaries of how Treasury evaluates and administers tax expenditures versus other fiscal tools.

Tax expenditure vs. direct spending — Both instruments deliver government support to a targeted activity, but through different mechanisms. Direct spending flows through congressional appropriations and appears as an outlay on the federal budget. A tax expenditure appears as a revenue reduction. The Congressional Budget Office's Tax Expenditures scoring methodology notes that functionally equivalent subsidies — one structured as a direct grant, the other as a refundable credit — produce identical distributional outcomes but are reported differently in budget accounting. Treasury has authority over the design of tax expenditures; the appropriations process governs direct spending.

Refundable vs. nonrefundable credits — A nonrefundable credit can reduce a taxpayer's liability to zero but cannot generate a refund payment. A refundable credit imposes no floor, allowing the excess to be paid out. From a budget perspective, the refundable portion of a credit is scored as an outlay rather than a revenue loss by the Office of Management and Budget, creating a classification boundary with administrative consequences.

Permanent provisions vs. temporary extenders — Congress periodically enacts time-limited tax incentives that require affirmative renewal, commonly called "tax extenders." Treasury must issue guidance for these provisions within compressed timelines, and their expiration creates compliance uncertainty. Provisions in the Tax Cuts and Jobs Act of 2017 (Pub. L. 115-97) included scheduled phase-downs — notably the reduction of bonus depreciation from 100% in 2022 to 60% in 2024 — creating predictable but legislatively determined decision points for taxpayers and Treasury guidance writers alike.

The broader architecture of Treasury's fiscal responsibilities, including tax regulation drafting and revenue collection, is documented in the overview of key Treasury dimensions and scopes.