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HMRC internal manual

National Insurance Manual

Class 1 NICs: reporting NICs in RTI: correction of errors under RTI: general

Social Security (Contributions) Regulations 2001, Schedule 4 paragraph 21E and 21F

Where an employer discovers an error in the calculation and/or reporting of NICs under RTI, the action they must take depends on whether it is:

  • in year - see NIM11531 
  • end of tax year (but before 20 April) - see NIM11531 
  • closed tax year, after 20 April - see NIM11533.