It's quite hard to hide a death in the UK. In hospital all deaths are certified, outside of hospital you have the interesting problem of how to deal with the corpse. And in addition to the death register there are also tax filings (including Council Tax, which is a hefty sum and paid monthly), utilities, and other services that require ID.

The media do print occasional Capitalist Gothic stories of people who kept a corpse in their house. But that's incredibly rare and - for obvious reasons - a high price to pay for a monthly cheque.