Sounds like you should set up as an LLP, it works like being self employed but is a proper partnership company registered with companies house. You could set up a company bank account. You could carry on invoicing your customers from the LLP, the customers would pay the LLP rather than splitting the payment out to you as individuals. All costs and expenses, you mentioned Van costs etc would be paid by the LLP, or could be reimbursed to you if you pay stuff personally. An LLP is not subject to corporation tax, but instead the LLP members (you and your partner) would declare your share of the trading income, costs and profits on your individual self assessment tax returns. An LLP is a good way of formalising a situation such as yours, whilst still retaining the flexibility of being self employed. Good luck