HMRC's official rate of interest has remained at 2.5% from 6 April 2017. It reduces to 2.25% from 6 April 2020.

Actual and average rates for earlier years:

 

Year	Rate %
2020/21 onwards	2.25
2017/18 to 2019/20	2.50
2015/16 to 2016/17	3.00
2014/15	3.25
2010/11 to 2013/14	4.00
2009/10	4.75