Since their privatisation in 1989, the 10 water companies have faced a periodic review every five years; it is undertaken by Ofwat, and prescribes customer prices, along with the investment requirements. As part of the ongoing review, PR19, Ofwat will publish its Final Determination numbers on 11 December 2019; they will apply as from April 2020, although water companies do have the option to seek a reference to the CMA.
