You are mixing figures here, OECD stats are for healthcare expenditures the UK currently spends about 12% of its GDP on healthcare and is aligned with most developed economies.

This is different to NHS funding alone.

Also comparing the UK where healthcare is predominantly a single payer system to countries like Germany isn’t apples to apples. Germany has a multi tiered private-public healthcare system and it’s not single payer.

Good point. But I can't make the numbers add up. If NHS is 7% and total health care is 12% then the NHS is only 58% of health spending, but how does it then make sense to say it's "predominantly single payer"? Looks to me like the private sector has exploded recently as people pay for private health care/insurance to cover the increasing gaps in the NHS coverage. This does nothing for those who are still just on the NHS.

This looks to be backed up by: "Based on trends observed in early estimates of household final consumption expenditure, household spending on outpatient and hospital services, which include self-funded and insurance-funded treatments, grew by 24.5% and 31.3% respectively in 2021." https://www.ons.gov.uk/peoplepopulationandcommunity/healthan...

But that link also says that NHS spending is 83% of health spending, so like I said I can't get the numbers to add up.

Because there are other things that go into healthcare that are accounted for in NHS funding such as hospices and elderly care.

The 83% in your link is the government spending on healthcare as % of total healthcare expenditure not the NHS budget as % of total expenditure.

The government funds other healthcare related expenses that aren’t direct NHS funding.