Food security is the major outcome of irrigation development activities. However, this cannot be achieved without sustainable water resources management. With the increasing budgetary constraints in many developing countries, governments have recognized the need to delegate irrigation scheme management to Irrigation Water Users’ Associations (IWUA’s) as much as possible. Despite the majority of these associations being operational, the major challenge has been poor performance due to inadequate farmer participation. This study examines the factors which influence farmers’ willingness to pay for irrigation water in a smallholder irrigation scheme in Kerio Valley Basin, Kenya. Using a multi-stage sampling method, a representative sample of 216 smallholder farmers from the Basin were interviewed. Results show that education level, access to training on irrigation, participation in construction of the irrigation system, crop income from irrigation and membership in IWUA significantly and positively influence farmers’ decisions to pay for irrigation water. Distance to the water source reduces the willingness to pay for irrigation water. Differential pricing based on income levels of farmers, rather than uniform pricing is recommended. We further recommend formulation of policies to train farmers in water management and to support farmer participation in IWUA’s.