The Check Employment Status for Tax (CEST) service is designed to determine whether an existing or future contract will be one of employment or self-employment.
CEST results are aligned with case law. Its results have been tested by HM Revenue and Customs (HMRC) against known case law and settled cases. HMRC published the list of cases that were used to test the accuracy of CEST on www.gov.uk/government/publications/cest-tool-tested-against-tax-cases/test-results-produced-after-cests-development.
CEST was rigorously tested throughout development with input from external stakeholders prior to release. The accuracy of CEST was checked as part of that process.
CEST was developed in accordance with government data standards. Government Digital Services (GDS) standards assessments are only required for transactional services. Because CEST is a tool for guidance purposes, and not a transactional service, a GDS assessment was not appropriate.
HMRC will stand by the result of CEST, provided the information entered is accurate and in line with HMRC guidance. CEST gives an answer in 85% of cases, and where it does not, more detailed guidance and support is available.
HMRC continues to improve the CEST tool and is working with stakeholders to better understand the points raised about CEST in responses to the recent consultation on addressing non-compliance with the off-payroll working rules in the private sector.