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HMRC internal manual

Labour Provider Guidance

HM Revenue & Customs
, see all updates

Systems and processes: HMRC information systems: direct tax: Self Assessment (SA)

Self assessment (SA) is the system used to log onto the records of self-employed individuals; company directors; partnerships and some other individuals. Returns are made on an annual basis, including nil returns.

It can be accessed from My Services/ Corporate Services/ ISSO

Choose a role and enter one of the following:

  • UTR or
  • NINO

SA is a way of calculating and paying tax. It does not generally relate to anyone who pays his or her tax solely through a PAYE scheme.

SA has its own help facility to navigate around the system and the SA manual explains the system in detail.

It is a ‘process now, check later’ system. Under this system taxpayers file returns and pay tax by prescribed dates. HMRC has a fixed period, (the enquiry window), in which to begin an enquiry to check the accuracy of a SA return.

The main risks are:

  • Failure to notify chargeability
  • Failure to make a return of a directorship
  • Making an incorrect/incomplete Return of Income and Gains
  • Failure to keep business records
  • Failure to pay correct liabilities

The objective of starting an enquiry is to seek information to check the accuracy and completeness of a SA return. SA shows the individual’s name and address; their tax and debt position and the returns made.

More information is available on the SA manual

SI process for setting up SA Director records via SESA

This process is specific to SI and refers to setting up a Self Assessment record for Directors only and has been approved and authorised by PT Operations.

All referrals should be made on a ‘SI to CAAT SESA Form’. The referral can be found using the following path:

SEES > XMLS forms > National Tab > Specialist Investigations > SI to CAAT SESA form.

A separate process for setting up Self Assessment records for Self-Employment Registrations is being developed; guidance will follow.