You do actually get plenty of time between when your financial year comes to a close and when the tax is due (10 months for self-employment, 9 months for limited company – if you don’t think this is enough, it is actually very generous compared to other EU countries and the US, who get 3 months and a half).
This means that you want to be predicting it as early as possible ideally every month. But it also means that you can confirm the tax amounts if you get your accounts info to your accountant early. Then the accountant can complete your accounts and confirm what the tax amount actually is.
In my firm, we encourage our clients to get their information to us within 3 months of the financial year end. It is bad enough having a conversation with a client when the tax bill is surprisingly high six months before the tax due but it is much worse having the same conversation a few days before it has to be paid.
Don’t let this happen to you, start estimating your tax as you go along and then get your estimate confirmed by your accountant way before the tax deadline.
