Whats the tax allowance if you have two businesses?

NJSims

I have a friend who currently is a sole trader and is looking to expand his skills by running another business that specializes in something else. What happens to his tax allowance? Is it split other the 2 business's? Forgive me, i'm new here.

CeeJaySix

Your personal allowance is your personal allowance. It doesn't get applied to each trade (or even trading income as a whole); it is deducted later in the computation from net income to give taxable income.