From 00:01 tomorrow, 21 December the Netherlands are reducing those permitted to enter the country. Those vaccinated, as well as those unvaccinated are required to quarantine for 10 days after arrival unless they test negative after 5 days. This day 5 test needs to be a PCR test.
This includes those arriving by any means of transport – bus, train, coach and plane.
The UK is classified as a High-Risk area.
Further information can be found from this link.