The general rule: limited liability protects you
A limited company is a distinct legal person, separate from its directors and shareholders. Corporation tax is a liability of the company, not of you personally, and in the ordinary course of business, if the company can't pay a tax bill, that's a company debt, not a personal one.
This protection is why most small business owners choose to trade through a limited company rather than as a sole trader. It holds even during an HMRC enquiry: the company answers for its return, and any additional tax, interest, or standard penalty is a liability of the company.

