What does limited liability actually protect you from?
Less than most people assume. A limited company is a separate legal person, so its debts are its own — but there are substantial and routine exceptions, and the ones that matter most are usually agreed to voluntarily.
The principle. Shareholders' liability is limited to the amount unpaid on their shares — frequently a nominal sum. If the company fails owing money, creditors claim against the company, not against the owners personally. Their homes and savings are not at risk.
The exceptions that apply in practice:
Personal guarantees. This is the big one. Banks, landlords, equipment lessors and many suppliers will simply require a director to guarantee the obligation personally before dealing with a small company. Once signed, limited liability provides no protection for that debt whatsoever. Most small business owners who lose money personally do so this way, and it is a contractual choice rather than a legal exception.
Wrongful trading. Continuing to trade when a director knew, or ought to have concluded, that there was no reasonable prospect of avoiding insolvent liquidation. A court can order a personal contribution to the company's assets.
Fraudulent trading, carrying civil and criminal consequences.
Misfeasance — breach of duty causing loss to the company.
Unlawful dividends. Dividends may only be paid from distributable profits. Paying them when there are none is unlawful, and directors can be required to repay — a genuinely common problem for owner-managed companies drawing dividends against an assumed profit that the year-end accounts do not support.
Certain taxes, where HMRC can transfer liability personally in defined circumstances, and unpaid PAYE and NIC in cases of deliberate behaviour.
Health and safety and other regulatory offences, where directors can be personally liable.
Your own negligence. Limited liability does not shield you from personal responsibility for your own acts.
What it never protects against: the practical consequences of failure, or the reputational effect.
What actually reduces personal risk: resisting personal guarantees, or negotiating limits and time expiry on them; taking early advice when solvency is doubtful, since the wrongful trading test turns on what you did when you should have known; keeping proper records; and appropriate insurance including directors' and officers' cover.
General information, not legal advice.