HMRC publish guidance on their website relating to how PAYE is operated and the legislation that you have to comply with. Not only do you collect and remit PAYE to the Collector of Taxes on behalf of HMRC, you also operate the sick pay scheme and maternity pay scheme. You should run the PAYE scheme in accordance with the legislation and should you fail to comply then HMRC will look to the employer for the tax or NIC you failed to deduct. This can be costly if you are unable to recover the tax and NIC from the employee.