Getting aSelf-Assessment Tax Return completed successfully requires you to maintain precise documentation of all your income statements together with expense records. The tax return system requires you to provide your payslips together with bank statements and details about rental income and investments and foreign earnings. People who operate their own business must provide their entire revenue with proof for expenses they can deduct. You should include all tax-deductible items which include pension contributions and charitable donations in your tax return. Your tax reference number serves as your essential personal identification for tax reporting. Allowed by tax law properly structured records assist both with efficient filing systems and prevention of mistakes which could trigger tax audits or enforcement actions. In most territories of the world you need to maintain your tax records over multiple years.