From May 2010 you may have to pay a penalty if you do not pay the PAYE due each month, on time and in full.
HMRC intend to implement the late payment penalties for payments due from May 2010. From then on, you may have to pay penalties if you make more than one PAYE payment late in a tax year. The penalties will be a percentage of the amount you pay late. They will start at 1 per cent and increase to 4 per cent depending on the number of late payments in a year. There are also penalties of 5 per cent if any of the PAYE due is still not paid after six months; and again after twelve months.
You should tell us as soon as you can, if you think you will have difficulty paying, otherwise HMRC may start recovery action.