The law states that all employees are entitled to an 'itemised pay statement' to accompany each payment of wages, setting out each element of pay, each deduction and the amount of net pay. Where wages vary depending on the number of hours worked (for example, under zero hours contract), the payslip must also show the number of hours for which you are being paid.
Information on fixed deductions, such as union subscriptions, or charity donations, do not need to be separately itemised and may be shown as a consolidated total, provided that a statement explaining the breakdown of each item is given to you at least every 12 months.
Additionally, each year your employer must give you a P60 certificate which shows your gross pay for the year, your take-home pay and the total deductions made during the year. You should expect to receive this shortly after the close of the tax year in early April.