Because Americans pay health insurance, a lot of people in the UK assume their ‘National Insurance’ pays for health. It doesn’t - NI pays for state pension and welfare benefits. The National Health Service is funded through general taxation and makes up around 20% of public spending. We pay for it mainly through income tax and VAT, but also fuel duty, alcohol and tobacco duty, and other taxes, plus indirectly though corporation tax. The average annual spend is about £4K per capita.