CrossCountry Accountants : December 2025 Welcome to this month’s edition of UK Tax and Accounting updates. With the Autumn Budget now delivered and the Finance Bill published, December is a pivotal month for businesses and individuals to digest new legislation and prepare for 2026. Below we highlight the most urgent developments and compliance actions. 1. Autumn Budget 2025 – Key Measures Now Law The Chancellor’s announcements on 26 November are now embedded in the Finance (No. 2) Bill 2024–26, published on 4 December2. Partnership NICs : Draft legislation confirms a new Employer-style NIC charge on LLP and partnership profits, effective April 2026. Firms should model the impact immediately. Capital Gains Tax (CGT) : Reforms include tighter rules on share reorganisations and Employee Ownership Trusts. Expect higher effective rates and reduced relief scope. Inheritance Tax (IHT): Anti-avoidance rules for trusts and non-long-term UK residents are introduced, alongside capped trust charg...