Public secondary schools in Kenya are expected to operate at affordable and sustainable costs. Despite this expectation, the cost of education in relative terms in most public secondary schools in Bomet County is still high. This may be an indicator that public schools are cost inefficient in their operations. The purpose of this study was to investigate the influence of school accommodation status on cost efficiency in public secondary schools in Bomet County, Kenya. The target population was two hundred and seventy principals of public secondary schools and all the five Sub-County Directors of Education in Bomet County. A sample of one hundred and seventy-five principals was selected using stratified and simple random sampling techniques. A semi-structured questionnaire was used to gather data from the principals and an interview schedule was used to solicit data from the Sub-County Directors of Education. The validity of instruments was examined using Content Validity Index. The study found that all variables had achieved Scalar-Content Validity Index of above 0.9 meaning that they were all valid and could thus be utilized in the study. The study results revealed that the Cronbach alpha coefficients of above 0.7 achieved for all variables imply that the variables had sufficient internal reliability to enable their usage in the study. The descriptive statistics including frequencies, means and standard deviations were used to analyze and summarize data. The simple linear regression analysis in inferential statistics was used to test the hypotheses in order to determine the extent to which cost efficiency could be predicted by school accommodation status, school size, and school type and school location. Statistical Packages for Social Sciences (SPSS) statistics version 25 software was used to perform only statistical operations on data analysis. The study found that the respondents agreed to a very small extent in respect to school incurring huge bills on water expenses, electricity expenses, food related expenses and teacher subsistence costs due to accommodation status. The study further found that the respondents were in agreement to a small extent on incurring huge bills on security expenses, administration costs, maintenance costs, transport costs, and subordinate staff costs on the account of school accommodation status. The study concluded that there was no statistically significant influence of the school accommodation status on the cost efficiency of public secondary schools in Bomet County. This was attributable to most of the schools within Bomet County being day schools and the cost indicators being examined having no major differences between day and boarding schools. Day schools in Bomet County need to improve on cost control in order to gain sufficient cost efficiencies in their operations.