What you need to do:
Gross Pay – enter your gross pay into the Income Tax Refund Calculator. This is the figure before any tax is deducted. The gross pay figure should include all PAYE income from all income sources and employment in that tax year.
Income Tax Paid – enter the amount of income tax you paid into the Income Tax Refund Calculator. The income tax figure should include all PAYE income tax paid from all sources of employment in that tax year.
Tax Year – the Tax Year begins on the 6th April in each tax year and stops on the 5th April the following year. For example the 2018/2019 tax year started on the 6th April 2018 and will end on the 5th April 2019.