Background Kenya's facility autonomy reforms are intended to improve health system equity, efficiency, and responsiveness to community needs by shifting decision-making to the frontline. This study evaluates the implementation process and experience of facility autonomy reforms in Kenya post devolution of health services. Methods We conducted a concurrent mixed methods study of counties (n=6) in Kenya, selected based on their implementation of facility financial autonomy reforms as of June 2023. For the quantitative aspect, we assessed 141 randomly selected public health facilities across all levels of service provision. We then did a descriptive analysis to measure the level and perceptions of autonomy. For the qualitative aspect, we reviewed documents and interviewed purposively selected stakeholders (n=71) involved with autonomy reforms at national, county, and facility levels, cutting across health, finance, legal, political and community actors. We analyzed the transcripts thematically using NVivo 12. Results The emergence of the FIF reforms in Kenya was driven by the convergence of political, technical, and public needs. While counties have developed their own facility autonomy laws to fit local contexts, some provisions are not fully aligned with the national legislation. Some aspects of both the county specific and national laws are not implemented. These include allocation of matching funds from the exchequer and reimbursing facilities for expenses incurred from providing care to indigents and for unpaid bills. The implementation of autonomy also varies, with some aspects partially or not implemented. Autonomy reforms have contributed to improved decision-making, staff satisfaction, availability of essential medicines, and facility maintenance. However, challenges have emerged, including the failure of counties to provide matching funds, which disproportionately affects lower-level facilities that do not generate revenue. Additionally, the absence of waiver repayment mechanisms has led to inequities, and the risk of increased service costs threatens financial accessibility for marginalized populations. Conclusion Facility autonomy reforms support people-centered decision-making and aligns with PHC principles. While these reforms hold promise for improving service delivery and access, their success depends on complementary measures such as sustainable funding mechanisms and stronger protections for vulnerable populations.