State Pension is a taxable income. However, as the Department for Work & Pensions (DWP) can't deduct tax from these payments we have to collect any tax due by reducing your tax free personal allowance.
For more information, go to the Pensions, state benefits and your tax code webpage.
You may be paid your State Pension at 4 weekly intervals. However, please provide the weekly amount that you are entitled to for 2016-17 in the amount box and not the amount that you receive every 4 weeks.