No. The lack of regulation in this market led to all kinds of shady practices which eventually led the Financial Conduct Authority (FCA) to ban self-certification of income.
In the current mortgage market, lenders will want to see a copy of the applicant’s certified accounts or if they file their own accounts, a copy of the HMRC website Tax Payable and the Tax Computation prepared by their accountant. Usually lenders wish to see the previous 3 years. The figure that lenders usually use the ‘net income’ figure which is clearly shown on the HMRC document.
Your annual Tax Payable information is available from the HMRC’s website.