In his Budget Speech on 3 March 2021 the Chancellor, Rishi Sunak, announced a number of changes to Corporation Tax.\nFirst the rate of CT will remain at 19% for the next 2 financial years until 1 April 2023 when it will be increased to 25%. However, this rate will only apply to those companies with profits above an Upper Threshold of \u00a3250,000. For companies with profits below a Lower Threshold of \u00a350,000 the rate of corporation tax will remain at 19%, then to be known as the Small Profits Rate. For companies with profits between the Lower and Upper thresholds there will be a marginal rate calculation effectively brining the rate closer to 25% as the profits approach \u00a3250,000.\nSecond a welcome extension to the loss relief rules, this extension will apply to a maximum \u00a32,000,000 of unused trading losses made in 2020\/21 and 2021\/22 by unincorporated businesses. For companies the \u00a32,000,000 maximum applies separately to unused trading losses, after carry-back to the preceding year, in relevant accounting periods ending between 1 April 2020 and 31 March 2021 and a separate maximum of\u202f\u00a32,000,000\u202ffor periods ending between 1 April 2021 and 31 March 2022.\nFinally, as previously announced the reduction in the temporary limit on the Annual Investment Allowance from \u00a31,000,000 to the permanent level of \u00a3200,000 due to take effect from 1 January 2021 has now been delayed by 12 months to 1 January 2022. In his Budget Speech the Chancellor has gone further and introduced a new Super-Deduction for companies investing in qualifying plant and machinery from 1 April 2021 up to and including 31 March 2023. This will be a first year allowance of 130% for main rate assets, and 50% for assets qualifying for special rate relief.