Failing to take out adequate employers' liability insurance is against the law and can have serious implications.
You can be fined  £2,500 for every day that you're not insured. You can also be fined £1,000 if you don't display your ELCI (Employers' Liability Compulsory Insurance) certificate or don't make it available to inspectors when they ask.  But it could cost you even more. In 2016, a takeaway shop was fined £4,360 in fines and legal costs for failing to produce an ELCI certificate.