Taxation is the imposition and collection of compulsory payments by government or other authorized public authorities. Unlike payment for a particular service, a tax normally provides no direct benefit proportional to the amount paid. Taxation transfers resources to the public sector and is a central subject of economics. Statistical definitions distinguish taxes from fines, compulsory loans, and many service charges, although boundaries depend on the nature of the payment. (oecd.org)
Purposes and scope
Taxes finance public expenditure, including infrastructure, education, administration, and social programs. They also influence the distribution of income and incentives to work, save, invest, and consume. These functions can interact: a measure intended to raise revenue may also change behavior, while an incentive intended to encourage investment may reduce collections. (imf.org)
Taxation is an instrument of fiscal policy. Income-sensitive taxes act as automatic stabilizers: collections generally decline when incomes fall and rise when incomes recover, cushioning fluctuations in disposable income without new legislation. Governments can also change taxes deliberately to influence aggregate demand. The effects depend on economic conditions, the measures chosen, and how expenditure responds. (imf.org)
Coverage differs among statistical systems. The OECD includes compulsory social security contributions paid to general government in tax revenue, but identifies them separately. Voluntary contributions and payments to institutions outside general government generally fall outside this definition. Consequently, comparisons require consistent treatment of contributions and levels of government. (oecd.org)
Main forms of taxation
Taxes can be classified by their base—the income, asset, transaction, or activity being taxed. Major categories include:
- Income taxes, imposed on individuals’ taxable income and businesses’ taxable profits.
- Property taxes, including recurring charges on real estate and taxes on certain transfers, inheritances, or net wealth.
- Consumption taxes, imposed on purchases of goods and services.
- Payroll taxes and social contributions, generally linked to employment earnings.
- Tariffs, imposed on goods crossing national borders, particularly imports. (oecd.org)
A value-added tax (VAT) collects consumption tax through successive production and distribution stages. Under the usual credit-invoice mechanism, registered businesses charge tax on sales and deduct eligible tax paid on purchases. This is designed to avoid cumulative taxation of intermediate inputs. A retail sales tax instead generally collects tax at the final sale, while an excise tax targets particular products or activities. (imf.org)
Tax bases and rates
A tax system specifies who is liable, what enters the base, the applicable rates, and available exemptions or reliefs. A deduction reduces taxable income; a credit reduces tax liability directly. These mechanisms therefore have different effects even when their stated monetary amounts are identical. (irs.gov)
The marginal rate applies to an additional unit of taxable income, whereas an average rate measures total liability relative to a specified income base. In a graduated bracket system, higher rates apply only to income within the relevant brackets, not automatically to all income. (irs.gov)
A progressive tax takes a rising proportion of income as income increases. A proportional tax takes a constant proportion, and a regressive tax takes a declining proportion. Assessments can differ according to whether the denominator is annual income, lifetime income, or expenditure. The distributional consequences of taxation also depend on transfers and the public services financed. (imf.org)
Incidence, efficiency, and equity
Tax incidence concerns who ultimately bears a tax’s economic burden, rather than who remits it. Businesses may adjust prices, wages, or returns to owners. In a standard competitive supply-and-demand model, the less responsive side of a transaction generally bears more of the burden. Price elasticity is therefore important in incidence analysis. Corporate taxes ultimately affect people, although the division among shareholders, workers, and consumers depends on circumstances. (imf.org)
Taxes can create a wedge between buyers’ payments and sellers’ receipts, discouraging otherwise beneficial transactions. The resulting deadweight loss is distinct from revenue transferred to government. Its size depends on behavioral responses, rates, and interactions with other taxes. Broad bases can permit lower rates, but taxing intermediate inputs can introduce production distortions. (imf.org)
Not all behavioral effects constitute efficiency losses. A Pigovian tax addresses an externality, such as pollution, by making private decisions reflect costs imposed on others. Equity is commonly divided into horizontal equity—similar treatment of similarly situated taxpayers—and vertical equity—differentiated treatment of taxpayers with different economic circumstances. These objectives can conflict with efficiency or administrative simplicity. (imf.org)
Administration and international taxation
Tax administration includes assessment, payment processing, verification, and enforcement. Systems may rely on taxpayer self-assessment, assessment by the revenue authority, or combinations of the two. Withholding and third-party reporting allow collection or verification using information supplied by employers and other intermediaries. (oecd.org)
Tax evasion involves non-compliance, such as concealing taxable sales or claiming false deductions. Tax avoidance generally reduces liability through arrangements that do not necessarily breach the rules as written; anti-avoidance provisions can restrict such arrangements. Errors, evasion, and organized fraud pose distinct administrative problems. (imf.org)
Cross-border activity creates overlapping taxing claims. Tax treaties allocate taxing rights and provide mechanisms to reduce double taxation. International cooperation also addresses base erosion and profit shifting, including arrangements that move taxable profits to low-tax locations with little corresponding economic activity or reduce taxable income through deductible cross-border payments. (oecd.org)