The U.K. has sold student loans to a variety of private investors and debt companies over the years. They tend to sell batches every few years where the Gov gets pence to the £ of their value, but it raises a few billion in ready cash
and stopped quite some time ago @SugarandSpiceandAllThingsNaice
The last sell off was a tranche of Plan 1 loans that entered repayment between 2007 and 2009 was completed in December 2018. In 2020 the Treasury stated:
The government has taken the decision that it will not proceed with further sales of student loans. As a result, no further sales of Plan 1 (pre-2012) student loans will now be undertaken. The government also has no plans to sell Plan 2 (post-2012) loans
Just a few weeks back the HoCL published its latest briefing on Student Loan Statistics. Section 6 specifically covers Student Loan sell offs.
https://commonslibrary.parliament.uk/research-briefings/sn01079/