R&D qualifying costs: Externally Provided Workers (EPWs)

Personnel costs are often the largest cost related to your R&D tax relief claim, and they fall within 3 categories of expenditure:

  • Staff payroll costs – for your internal staff
  • Externally Provided Workers (EPWs) for your supplementary staffing needs, which we’ll cover here
  • Contractors – for contracted out R&D

In this article, we will cover the key aspects of EPWs, including their definition, restrictions, and how we calculate R&D tax relief in relation to these costs.

What is an EPW in relation to your R&D tax relief claim?

EPWs are an integral part in your commercial and R&D needs; they are seen as a temporary extension to your internal staff and are supplied by third-party agencies.

EPWs are distinct from regular employees and contractors due to their temporary nature and the involvement of a third-party provider. This allows companies to flexibly manage their workforce without the long-term commitments associated with direct employment.

What is the definition of an EPW for R&D tax relief claims?

EPWs are individuals who provide services to a company but are not its employees or directors. They are typically supplied by a staff provider, such as a staff agency. To qualify as an EPW, 7 conditions must be met:

A person is an externally provided worker in relation to the claimant company if the following conditions are satisfied:

  1. The worker must be an individual (not a company)
  2. The worker cannot be a director or employee of the company
  3. The worker must personally provide, or is under an obligation personally to provide, services to the company
  4. The worker must be subject to (or to the right of) supervision, direction, or control by the company as to the manner in which those services are provided
  5. The worker’s services are supplied to the company through a staff provider or staff controller (whether or not they are a director or employee of the staff provider or staff controller or any other person)
  6. The worker provides, or is under an obligation to provide, those services personally to the company under the terms of a contract between the worker and a person other than the company (the “staff provider”)
  7. The provision of those services does not constitute the carrying on of activities contracted out by the company

Restrictions on EPWs

From 1 April 2024, expenditure on overseas EPWs does not qualify for R&D tax relief. This change aims to encourage the use of local talent and resources.

Connected vs. Unconnected EPWs

Unconnected EPWs

If the staff provider is not connected to the claimant company, only 65% of the expenditure paid to the staff provider can be treated as qualifying expenditure, this accounts for any profit margin included in the cost. By way of an example, if £100,000 is paid to a staff provider, only £65,000 can be considered when calculating your R&D claim.

Connected EPWs

If the staff provider is connected to the claimant company, the company may claim the lower of the qualifying payment for staff made to the staff provider or the actual eligible cost of the relevant staff incurred by the staff provider. An example of a connected EPW provider is a subsidiary company.
Understanding the difference between connected and unconnected providers is vital to ensure accurate R&D claims.

Summary

Understanding the conditions and eligibility for EPW costs is vital if you want to maximise your R&D tax relief claim in a robust and compliant manner.

Reviewed by Deborah Chapple, Q&R Director | 22 September 2025

Contact us to find out how you can make the most of your claim