UK Supreme Court confirms narrower interpretation of salaried members rules in HMRC v BlueCrest, with significant implications for LLP partner taxation

The UK Supreme Court gave judgment on 1 July 2026 in HMRC v BlueCrest Capital Management (UK) LLP, providing important guidance on when members of a limited liability partnership (LLP) should be taxed as employees rather than as self-employed partners under the salaried members rules in the Income Tax (Trading and Other Income) Act 2005. The salaried members rules, introduced to prevent LLPs from using the partnership structure to secure more favourable tax treatment for what are in substance employees, apply where three conditions are met. The case turned principally on Condition B, which asks whether the member has significant influence over the affairs of the LLP. The Supreme Court confirmed a narrower approach to Condition B than some lower tribunals had adopted. The Tax Tribunal had dismissed BlueCrest's appeal on Condition A but allowed it on Condition B in respect of desk heads and portfolio managers with capital allocations exceeding $100 million. The Supreme Court unanimously dismissed BlueCrest's appeal on both Condition A and Condition B. Its judgment focused on the meaning of "significant influence" over the affairs of an LLP, confirming an interpretation that, in practice, makes it easier for HMRC to treat high-earning LLP members as salaried: qualifying influence must derive from legally enforceable rights under the LLP's contractual and statutory framework, and must bear on the affairs of the LLP as a whole at a strategic level, rather than on a member's own operational or trading activities. The case returns to the First-tier Tribunal to reconsider Condition B on that basis. The decision carries direct relevance for law firms, private equity houses, investment managers, and other professional services businesses structured as LLPs, many of which have been monitoring the case closely given the potential scope of HMRC's claimed taxing power over their partner populations. No external law firm advisers were named in the sourced reporting.