If you are self-employed, you can claim back expenses against your income to reduce your overall business profit and the amount of tax you pay.
For example, if you earn £40,000 through self-employment and claim back £5,000 in allowable expenses, your profit will be £35,000, so you will only pay tax on this.
Many of these allowable expenses are obvious. And if you have been self-employed for a few years you will know most of them. But there are certain less obvious expenses that you might not have claimed for.