UK: the NHS is funded from the general pot of government income, and takes up roughly 18-20% of government expenditure. I haven’t updated my back-of-an-envelope calculations recently, but a couple of years ago I worked out that 18% of income tax and National Insurance contributions for people in employment worked out at somewhere around 4-5% of gross income, more or less up the salary scale from the median household income to at least £150,000 p.a.
People below certain income levels don’t pay either of those, of course, and people in retirement like me don’t pay NI. My recent tax summary statement from the Revenue tells me I paid £903 in income tax for the government’s health budget, which is less than 3% of my gross income, which is just above the median household income. Because I’m retired, I also get my prescriptions completely free of charge, where most people pay something like £8 per NHS prescription.
On top of that there would be slightly less than 4% of whatever VAT one pays on relevant goods, and 18% of whatever additional duties are paid on e.g., fuel, alcohol, tobacco, insurance premiums, betting, flight departures (basically. not particularly noticeable).
There is always debate about adjusting rates, and so on, maybe that better-off pensioners like me should go on paying National Insurance contributions, or the same prescription charges as working adults. Sometimes people propose a ring-fenced or “hypothecated” tax charge for the NHS, but our treasury traditionally hates ring-fencing income streams, so it would take a major political effort to bring in something like that.
I’ve never had private medical insurance (probably couldn’t get it now, except at prohibitive rates), but I’ve never felt the need to, and am happy to stick to NHS provision. Living in London, I probably have access to a wider range of provision than people in some other parts of the country, and fortunately have never had particularly difficult or complicated issues to be dealt with: but I don’t feel it’s difficult to get a routine appointment with the local GP practice, and the few occasions when they wanted to refer me on to specialist advice, it didn’t seem like too long a wait, maybe ten days to a fortnight.