HMRC usage data shows 48% of Feb-21 CEST determinations are outside IR35

HMRC has just published details of CEST usage up to the end of February 2021.


The latest stats show a total of 1,214,229 CEST uses from 25 November 2019 to 28 February 2021. This breaks down into the following user groups:

  • 42% workers
  • 56% end clients 
  • 2% agencies

February 21 saw a total of 119,364 CEST uses, an increase of 45% on the January 21 figure of 65,684 uses. This uptake shows what we expected – a rush by end clients to make status determinations leading up to the 5th April deadline.   

Contrary to popular belief, not every CEST determination is inside IR35! A positive contractors can take away from the data is the high number of outside IR35 determinations.  

In uses by end clients, 48% of CEST determinations were classed as outside off-payroll working rules (IR35).

However, the number of ‘Undetermined’ results accounts for over a fifth of uses. 

Interestingly, 64% of the total ‘Undetermined’ CEST determinations in February were made by end clients. This further reinforces the need for clients to communicate with contractors to understand their working practices, and for contractors to be proactive and influence hiring managers.     

The full Check Employment Status for Tax (CEST) usage data report from HMRC is available here.