If you don't have all your tax money saved, that leads to the question of where it has gone. If you've simply taken it out of the company and spent it, then there is good possibility that you have an overdrawn directors loan account. If you've taken illegal dividends, that would have the same result.
There are two tax consequences following from that. The first is that you might have a P11d taxable benefit on the notional loan interst (and fines for not filing the P11d on time) The second is that the overdrawn loan account, if not repaid within 9 months can attract a further corporation tax charge at 25% of the overdrawn balance. That's a temporary cost, which can be recovered later on if the loan is repaid, but the tax has to be paid nonetheless.
