This is a issue that is affecting every dental practice across the country and dental solicitors specialist advisers (lawyers and accountants) have been paying close attention to it.  The categories listed below are those referred to by HMRC.

The CEST tool can be used by either the worker (the associate dentist) or the hirer (the dental practice), and can also be used to determine whether the worker is an employee or self-employed, or a worker operating through a limited company, and if they fall under the off-payroll working (IR35) rules or not.

Below are some of the questions that are relevant to the dental principal-associate contractual arrangement.

The Work

The first section of the CEST tool asks if you are looking at whether IR35 applies (a contract with an associate dentist operating through a limited company), or whether you are looking at if the work will be classed as self-employment. The answer to this will depend on how the associate is being engaged.

Our comments are based on the position of the Principal of the dental practice and a situation where the associate dentist is already working at the dental practice.

Worker’s duties

The CEST tool asks whether the associate dentist will be an office holder. An office holder is a company secretary or company director of the dental practice if the dental practice is trading as a limited company. The answer for this will be no.

Substitutes and helpers

This is important for determining whether the associate dentist will be self-employed. This part asks whether the associate has ever engaged a substitute to carry out the work, whether the dental practice has the right to reject the substitute and whether the associate dentist has ever paid another person to carry out the work for them.

Our response is based on the fact that contractually the Principal/Practice has the right to reject the substitute, even if in reality, this is unlikely. If the associate dentist has previously engaged a locum to carry out their work, for example if they were off work with illness or on parental leave, the test will then ask who actually paid the locum.

It is important that the questions are answered according to the actual working practices and not the contract. If the contract states the associate dentist will need to engage the locum, but the dental practice found the locum and paid them, then the question should be answered in accordance with the actual working practice.

Working arrangements – Control

The CEST questions in this section include:

  • Does your organisation have the right to move the worker from the task they originally agreed to do?
  • Does your organisation have the right to decide how the work is done?
  • Does your organisation have the right to decide the worker’s working hours?
  • Does your organisation have the right to decide where the worker does the work?

The associate dentist is engaged to carry out dental services on the dental practice’s patients. The dentist would not be moved from this task to carry out other tasks, such as reception duties, and the first question isn’t a particular concern for the ordinary working arrangement.

The associate dentist is a highly skilled professional and the principal dentist will not decide how the associate treats their patients and so the answer to the second question would state that the worker is highly skilled.

It is likely that the dental practice will determine the working hours, as the dental practice will be open on certain days of the week with standard opening hours. The place of work will also be the dental practice building, and so there is only one place for the associate dentist to work in.

Workers financial risk

This section is arguably the most important section to determine self-employment.

The relevant questions are as follows:

  • Will the worker have to buy equipment before your organisation pays them?
  • Will the worker have to fund any other costs before your organisation pays them?
  • How will the worker be paid for this work?
  • If your organisation was not happy with the work, would the worker have to put it right?

An example is that Associate dentists will have their own loupes that they have purchased to enable them to carry out dental treatment and may have other equipment they use that is not funded by the dental practice. Without these, the associate dentist would not be able to carry out treatment and so would not be paid.

The associate dentist will need to fund other costs – these include professional indemnity insurance, GDC subscription and other costs.

Most associate dentists are paid a percentage of the work they perform and this is important in order to reach a  decision of self-employment. If the dental practice is paying the associate a fixed hourly rate, which would be in a small minority of cases, we would suggest that this is changed as it could affect the final decision.

The final question can be looked at in the scenario of a patient being unhappy with the treatment they have received. In most contracts, the associate dentist will need to fix the problem with no additional fee being paid by the patient and so the associate dentist will effectively generate no income during that treatment time. The associate dentist may also incur additional laboratory costs that may not be shared by the dental practice depending on the terms in the contract.

Workers involvement

This section looks at what benefits the practice provides to the associate, whether they have management responsibilities and how they introduce themselves to patients.

HMRC describe management responsibilities as giving appraisals to employees, hiring and firing employees and helping decide on how much to pay someone. It is unlikely an associate dentist will have management responsibilities at most dental practices and as a self-employed individual, the associate dentist should not have management responsibilities.

The CEST tool asks how the associate dentist introduces themselves to consumers/suppliers and can be answered as working for you, an independent worker acting on your behalf, work for their own business or this would not happen. An associate dentist is working for their own business in the dental practice premises, but it is unlikely a patient is aware of the working arrangement. 

Workers contracts

This final section looks at the contract, whether there are any ownership rights in the contract or restrictions of trade and previous and future contracts. Most associate contracts will include some restrictions on the associate being able to work within a certain radius of the dental practice.

The answers to some of these questions will depend on the contract in place and whether the associate dentist is also working at more than one dental practice.


Once the questions are answered, the CEST tool will ask you to check your answers and then give you a result of either employment, self-employment or cannot determine the status.

The workers financial risks section is the most important section in determining whether the engagement is self-employed. If the associate is paid a percentage of treatment undertaken, funds some of their own costs, or funds some of their own equipment costs, the result will generally be that of self-employment. If the answers to these questions are amended, then the CEST tool may change the result to unable to make a determination.

HMRC have stated that where the questions are answered truthfully and accurately then they will accept the determination that arises.

The dental practice should keep a copy of the results with the contract for the associate and if the CEST tool is updated, the working arrangement should again be tested on CEST.