A tax deduction is an expense that can be subtracted from an individual’s total taxable income, thereby reducing the amount of income subject to taxation. Common deductions include those for mortgage interest, medical expenses, charitable donations, and certain education costs. By lowering taxable income, deductions help taxpayers decrease the overall tax liability they owe to the government. Each country’s tax laws outline specific rules and limits for what qualifies as a deductible expense. Proper use of tax deductions can result in significant savings during tax filing.