You are legally required to take out Employer’s Liability (EL) insurance if you employee anyone, even on a casual basis. This is the only insurance that is illegal required to operate your business with in the UK. Some contractors will request you have EL insurance, ensure this is clarified in the contract between you before starting to work with them. If you have employees and operate without EL insurance you could receive a fine of up to £2,500 per day.