HMRC plan to switch on the self-assessment autocoding functionality of the National Insurance and PAYE Service (NPS) early in 2011/12.
The move will allow relevant information to flow from a self-assessment return with a PAYE source to NPS, and then automatically calculate and issue revised codes.
HMRC say the system will not override codes that have already been adjusted for 2011/12 following contact from a taxpayer, although additional information provided in the return will be used.