Inaccessibility to extension services by smallholder farmers remains one of the impediments to achieving high agricultural productivity and food security. Extension services play a critical role in information dissemination that can avert food insecurity and increase smallholder dairy farmers' incomes. However, access to extension services remains a significant challenge in developing countries. This study investigated the influence of access to extension services on milk productivity among smallholder dairy farmers in Njoro Sub-County, Nakuru County, Kenya. The study's target and accessible population was 17,000 smallholder dairy farmers. The study used simple random and proportionate sampling techniques to select study farmers. Nassiuma's formula generated a sample of 120 smallholder dairy farmers. The hypothesis underwent testing using simple linear regression. The regression results found a statistically significant influence between access to extension services and milk productivity at a 5% significance level (p < 0.05). Findings show that most smallholder dairy farmers accessed extension services through television, radio, neighbours, and friends. In contrast, the top animal husbandry practices that most farmers were interested in were parasite and disease control, breed selection, and feed preparation. The Government of Kenya mainly provided vaccination services, while the other veterinary services, including deworming, pregnancy and disease diagnosis, breed selection, and treatment, were dominated by private entities. The Government of Kenya should improve smallholder dairy farmers' access to extension services. The study recommends channeling agricultural information in all possible vernacular languages and Kiswahili, the national language, via television and radio platforms to reach all smallholder dairy cow farmers. Additionally, more emphasis should be on the importance of appropriate milking techniques and record-keeping among smallholder dairy farmers to help monitor their animals' health, feeding, breeding, and milk productivity.