https://www.congress.gov/crs-product/RS22331
As of 2024, 70% of debt is owed domestically, i.e. bonds are owned primarily by people within the US. Only 30% of US debt is owned by foreign interests.
Foreign debt is mostly owned by Japan:
- Japan, $1,061 billion, 12.4% of foreign debt
- China, $759 billion, 8.87%
- United Kingdom, $722 billion, 8.44%
It's only when you group together all "European countries" that they collectively hold the most debt.
Here's a more updated figure from 2025:

It seems like a trend right now is that China is divesting from the US:
Beijing’s stockpile fell to US$682.6 billion in November, down from US$688.7 billion in October, according to US Treasury Department data released on Thursday.
That marks the lowest level since September 2008 and a nearly 10 per cent drop since last January, according to financial data provider Wind.

