If you are just selling some unwanted items that have been lying around in the attic, the answer is probably no. In order to pay tax on the goods you sell, you either have to be trading or make a capital gain. If you are trading you will be self-employed.
Essentially ‘trade’ is a two-way relationship between a trader and a customer – where the trader provides goods or services to the customer for reward on a commercial basis. In addition, the courts have identified ‘nine indicators or ‘badges’ to help decide whether a trade exists or not. It is not always easy to decide even using these ‘badges’ because a trade may exist even if only one or two of the indicators are present.
You are trading if you:
If you are trading you may have to pay Income Tax and National Insurance Contributions (NICs) and VAT, and we will treat you as self-employed in that trade.
But you are not trading if you:
If you are not liable to Income Tax you may still be liable to other taxes.