School districts across the United States are increasingly adopting the four-day school week, often in the hope of addressing teacher staffing challenges. We examine the effects of the four-day week on non-teacher staffing and recruitment, and schoolwide expenditures in Missouri, where three in ten districts currently use it. Using a difference-in-differences design to identify the causal impact of four-day school week adoption, we find limited evidence that the policy impacts non-teacher staffing, nor do we find practically meaningful effects on retention. While we do see savings in some budget areas (e.g., operations), we observe an increase in tuition payments. Thus, overall, our findings suggest that four-day school week adoption does not result in meaningfully significant positive impacts on non-teacher staffing or retention, nor on schoolwide expenditures.