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What is “Supervision, Direction or Control” (SDC)

 

Supervision, Direction and Control (SDC) is an important consideration when determining whether a worker may qualify for tax relief on eligible mileage expenses when working through an employment intermediary, such as SmartWork.

If you work through an employment agency or umbrella company, understanding SDC can help you understand how your assignment is assessed, how your expenses may be treated for tax purposes, and what information your end client may require.

At SmartWork, we follow an assessment process to help determine whether a worker is subject to SDC, or has the right to be subject to it, in relation to their assignment.

What Is Supervision, Direction and Control (SDC)?

Supervision, Direction and Control refers to the extent to which another party has the authority or right to oversee, instruct, or control how a worker carries out their duties.

For employment tax purposes, the assessment considers three areas: supervision, direction and control.

Supervision – Supervision involves overseeing a worker’s duties to ensure that work is completed correctly, meets the required standard and follows agreed expectations. Examples may include:

  • Monitoring the quality or progress of work.
  • Reviewing completed tasks.
  • Providing guidance or feedback on how duties should be performed.

Direction – Direction involves providing instructions, guidance or information about how a worker should carry out their duties. Examples may include:

  • Explaining the methods or procedures a worker must follow.
  • Instructing a worker on the order in which tasks should be completed.
  • Providing specific instructions about how particular duties must be performed.

Control – Control is the authority to determine what work a worker does, how they do it, and when and where it must be completed. Examples may include:

  • Deciding which duties a worker must undertake.
  • Determining the working methods or procedures to be followed.
  • Having the authority to change a worker’s assigned tasks.

The right to exercise SDC is important. A worker may be subject to SDC even if supervision or instructions are not routinely provided. The assessment considers the relevant rights and arrangements, not just the level of day-to-day oversight.

Why Does SDC Matter?

SDC can affect whether a worker is eligible for tax relief on certain employment-related expenses when working through an employment intermediary. Where a worker is subject to supervision, direction or control, or has the right to be subject to it, tax relief on travel and subsistence expenses may be restricted under the relevant rules.

For SmartWork workers, the SDC assessment is particularly important when determining whether eligible business mileage expenses can be processed with tax relief through SmartWork. The outcome depends on the circumstances of the assignment, the available evidence and the applicable tax rules. Completing an SDC questionnaire does not automatically establish eligibility for tax relief.

How Does SmartWork Assess SDC Status?

When you join SmartWork, your assignment is initially treated as subject to Supervision, Direction and Control (SDC). If you believe your assignment is not subject to SDC, you can complete the SmartWork SDC questionnaire to provide information about your working arrangements.

Our assessment process includes the following steps:

1. Complete the SDC questionnaire – You will be asked questions about your role, duties and working arrangements, including the extent to which another party may supervise, direct or control your work. It is important to answer each question accurately and provide enough detail for your circumstances to be assessed. The questionnaire provides initial information to support the assessment, but it does not guarantee a particular outcome.

2. Review the relevant employment documents – SmartWork reviews the information provided alongside relevant employment documentation, including your Contract of Employment and Assignment Schedule. The assessment considers the contractual arrangements and the information available about how your assignment operates in practice.

3. Obtain written confirmation from the end client – Where required, SmartWork will request written confirmation from an appropriately authorised representative of your end client. The end client may be asked to confirm whether they agree with the initial assessment and provide information about the working arrangements, including whether they have the right to exercise supervision, direction or control over your duties.

4. Finalise the assessment – SmartWork reviews the questionnaire, relevant documents and end-client confirmation before reaching a conclusion. If information is incomplete or the evidence does not provide a sufficiently clear picture, we may request additional details before confirming your SDC status.

How Does SDC Affect Mileage and Expenses?

Your SDC assessment determines whether SmartWork can process eligible business mileage expenses with tax relief under its non-SDC arrangement.

If you are confirmed not to be subject to SDC, SmartWork may process eligible business mileage expenses with tax relief, provided you meet the applicable rules and supply the required supporting evidence. All other expenses must be claimed directly from HMRC at the end of the tax year, using form P87 or Self Assessment, as appropriate. Any claim remains subject to HMRC’s eligibility requirements.

If you are subject to SDC, SmartWork cannot process mileage expenses with tax relief under the non-SDC arrangement for the relevant assignment. Check the applicable HMRC rules to determine whether you can claim any expenses directly from HMRC. Eligibility depends on your circumstances and the relevant tax rules.

If your assessment is not yet complete, and we need more information or end-client confirmation, we can’t confirm your SDC status as non-SDC until we’ve reviewed the required evidence. Please do not assume you qualify for tax relief on mileage expenses until SmartWork completes the assessment and confirms the outcome.

Does SDC Apply to Skilled or Specialist Workers?

SDC is assessed according to the circumstances of the individual assignment. Specialist qualifications, professional experience, or a high degree of technical knowledge do not automatically mean a worker falls outside the SDC rules. For example, a professional may have discretion over technical decisions but still have to follow instructions, procedures, or working arrangements set by another party. The assessment therefore considers the relevant rights and arrangements rather than relying solely on a job title, skill level or the amount of supervision provided in practice.

 

 

Frequently Asked Questions About Supervision, Direction and Control (SDC)

Does completing the SDC questionnaire guarantee tax relief?

No. The questionnaire is only the first part of the assessment. SmartWork also need to review relevant employment documents and obtain written confirmation from an authorised end-client representative before reaching a conclusion.

Can I claim mileage through SmartWork if I am not subject to SDC?

Potentially, yes. If SmartWork confirms you are not subject to SDC, it may process eligible business mileage expenses with tax relief, provided you meet the applicable rules and supporting evidence requirements.

Can I claim other expenses through SmartWork?

Under SmartWork’s SDC process, you can claim tax relief only for eligible business mileage expenses when you are confirmed not to be subject to SDC. All other expenses must be claimed directly from HMRC at the end of the tax year, using form P87 or Self Assessment, as appropriate. Claims are subject to HMRC’s eligibility requirements.

Who confirms whether I am subject to SDC?

SmartWork assesses the available evidence, including your questionnaires, relevant employment documentation, and written confirmation from an appropriately authorised end-client representative. Your final assessment depends on the evidence and the circumstances of your assignment.

What happens if my end client disagrees with my questionnaire?

SmartWork may request further information to clarify the working arrangements. The assessment will consider the available evidence before confirming an outcome.

 

For more detailed guidance from HMRC on SDC, please refer to this HMRC link.