Tax and NICs implications for businesses having a globally mobile workforce

Host employer provisions (HEP) are in the spotlight yet again. 

By way of reminder, where an individual is employed by a foreign employer (not resident or present in Great Britain), the personal service of that individual is made available to a host employer, and the service is rendered for the purposes of the host employer’s business, then the host employer is deemed the ‘secondary contributor’ for NICs purposes. 

HMRC is currently litigating four cases where it has sought to apply these rules; in each, a UK entity transferred the employment of offshore workers to an offshore entity, which then supplied the workers back to the UK entity to work on installations on the UK continental shelf. You can read more in our Tax Journal article: How to be a good host (employer): it’s all in the detail.

In one of those cases, Aramark v HMRC [2026] UKUT 00348 (TCC), the Upper Tribunal (UT) in has since upheld the First-tier Tribunal’s (FTT) conclusion that Aramark was liable for secondary Class 1 NICs under the HEP on the basis that workers’ personal services were made available to Aramark and rendered for the purposes of its business. Applying reasoning from earlier case law, the UT rejected the argument that the HEP required Aramark to exercise day-to-day control before the provision could apply; but it also held that, even if control had been required, the FTT had been entitled to find on the facts that Aramark exercised the relevant operational control and that the offshore employer was little more than a contractual shell. The appeal was therefore dismissed.

The decision is another clear signal that international employment structures are firmly on HMRC’s radar and that HMRC is continuing to sharpen its focus across cross-border employment models more generally. 

That scrutiny can be seen not only in litigation, but also in HMRC’s continuing crackdowns on umbrella company structures, including offshore structures, and its recent focus on guidance setting out its approach to globally mobile employees. For example, HMRC has published guidelines on income tax and NICs treatment for short-term business visitors to the UK, and we understand that a new International NICs manual is under development and will be published in due course. In addition, as set out in more detail in our recent insight article, HMRC is currently reviewing two long-standing administrative concessions affecting directors and employees based abroad: firstly, the concession allowing non-resident directors to carry out limited UK duties without a NICs liability; and secondly, the NICs easement for certain employees posted to countries with which the UK has no social security agreement, permitting short return visits to the UK without triggering additional Class 1 NICs. 

Taken together, these developments point to a much more structured compliance environment to come for employers using internationally mobile workforces. This is an area to watch closely as further developments are likely to follow.