United Kingdom competition law

No problem with having a monopoly. The issue is with 'abuse of a dominant position' which requires a monopoly (for collusive behaviour the law is slightly different).

Having a monopoly by itself is not a breach of UK/EU competition law (which are essentially one and the same thing).

See Treaty on the Functioning of the European Union Articles 101 and 102, and sections 2 and 18 of the Competition Act 1998.

The sort of behaviour that would be caught by section 18 of the Competition Act (abuse of a dominant position) would include raising prices because there is no competition or putting in other unfair terms into the contract, or applying different conditions to essentially the same contracts for no reason other than 'you can' (i.e., there is nowhere else for you to go so you take it or you're stuffed).

Generally these things are quite difficult to investigate and so the Competition and Markets Authority (CMA) will only be concerned if the case is big enough.

You can complain to the CMA here - https://www.gov.uk/government/public...ues-to-the-cma but I wouldn't hold out too much hope.

Surely, as well, there is relatively little barrier to entry, if say Aviva or one of the Lloyds of London insurance guys wanted to start offering it they could without much difficulty. The fact they don't indicates that it is not very profitable at current prices, which would imply that they are not abusing their dominant position.