It is expected that he will announce the reform of capital gain tax (CGT) which we expected during the Autumn Statement in 2020 that was cancelled.  The new rules could be in place by the 6th April.  Entrepreneurs are worried that the CGT rates could be aligned much more closely with the income tax system.  Currently, most taxpayers pay CGT at a rate of 20%, falling to 10% for basic-rate taxpayers. By contrast, higher- and additional-rate taxpayers pay 40% and 45% respectively on their incomes. Increasing CGT accordingly – and perhaps introducing a new additional rate

There is also the possibility that The Chancellor could abolish Entrepreneurs Relief that allows business owners reduced CGT of 10% o the first £1m of capital gains they make when selling their business.