Tax Incidence

Tax incidence distinguishes between the statutory incidence of a tax (who is legally obligated to remit it to the government) and its economic incidence (who actually bears the cost through reduced income, higher prices, or lower returns). The two often diverge because taxed parties can shift burdens onto others through price adjustments.

The core insight of incidence analysis is that the distribution of the burden depends on the relative price elasticities of supply and demand, not on which side of the market the tax is collected from. The more inelastic side—the one less able to change its behavior in response to price—bears more of the burden. For example, if demand for cigarettes is highly inelastic, consumers absorb most of an excise tax even if it is legally levied on producers.

Incidence can be analyzed in partial equilibrium (one market in isolation) or general equilibrium (accounting for spillovers across markets and factor returns). Arnold Harberger's 1962 model of the corporate income tax was a landmark general-equilibrium analysis showing that shareholders may not bear the full burden; portions can shift to workers or consumers depending on capital mobility.

Key applications in policy debates include:

• Payroll taxes: although nominally split between employers and employees, most empirical studies find workers bear the bulk through lower wages.
• Corporate taxes: ongoing debate about how much falls on capital owners versus labor, with estimates varying widely.
• Tariffs: studies of the 2018–2019 U.S. tariffs on Chinese imports (Amiti, Redding, and Weinstein 2019; Fajgelbaum et al. 2020) found nearly complete pass-through to U.S. importers and consumers.
• Excise taxes on tobacco, alcohol, and sugar-sweetened beverages, where incidence shapes both revenue and public-health outcomes.

For policymakers and researchers, incidence analysis is essential for evaluating the distributional fairness of a tax system, since headline statutory rates can be misleading about who actually pays.