Useful links to forms and notes:
Our guides:

P11D: which form? Links to different versions of the forms

P11D: top tips tool kit Guide and checklist for completing forms P11D and P9D (up to 5 April 2016)

PIIDs: penalties

PAYE: P11D dispensations  (up to 5 April 2016)

Late payment of Class 1A NICS, see: PAYE late payment penalties

Also see Payrolling of Benefits