If you have missed the 31 January 2018 deadline for the submission of your income tax return for the year ended 5 April 2017, then the next deadline is 2 March 2018, when you may be charged a penalty of 5% of any tax that is due. We recommend that you see an accountant at once.
If you engage us, then we would request an advance on our fee of 50%, and the balance once you have signed the accounts and tax return. We have lots of new technology and we have the speed, but we want to be fair to everybody. Other accountants might still give you credit.