The view that people in similar circumstances should be treated equally and that differences in needs should be reflected by differences in treatment. Applying this concept to the tax system, for example, it would appear unjust to tax two similar workers at different rates. Some might argue on similar grounds that it is unjust to impose the same taxes on people with burdensome obligations such as mortgage payments as on other taxpayers with equal incomes but no similar obligations. Horizontal equity is distinguished from vertical equity, which is concerned with questions such as how far large differences in income should be moderated by redistributive taxation.

• uncompetitive
• UNCTAD
• undated security
• under-capitalized
• under-developed country
• under-funded pension scheme
• underlying rate of inflation
• under-subscription
• under-valued currency
• underwriting
• undistributed profits
• UNDP
• unearned income
• unemployable
• unemployment
• unemployment benefit
• unemployment rate
• unexpected inflation
• unfair competition
• unfair dismissal
• unfunded pension scheme
• unified budget
• uniform business rate
• uniform distribution
• union