The Water Sector Trust Fund (WaterFund) is a Kenyan State Corporation under the Ministry of Water and Sanitation and established under the Water Act, 2016, with the mandate to provide conditional and unconditional grants to the Counties and to assist in financing the development of and management of water services in the marginalised and underserved areas.

It previously existed as the Water Services Trust Fund prior to the repeal of the Water Act, 2002, which had established it.