As global challenges escalate—economic shocks, environmental issues, and evolving work expectations—the four-day workweek (4DWW) is gaining traction as a sustainable and viable alternative. This study investigates the transition from a traditional 5-day workweek to a 4DWW in the context of private companies in the Baltic States, supplemented by the insights from informal interviews with 17 representatives across Latvia, Lithuania, and Estonia and an in-depth case study of a Latvian wholesale company. Employing a mixed-methods approach, the research integrates document analysis, structured interviews, and quantitative assessment of key performance indicators over an 8-year period. The findings elucidate the phased transition process, detailing the multifaceted challenges encountered at individual, operational, and strategic levels. The study evaluates the impact of the 4DWW on organizational productivity, employee well-being, and environmental outcomes. Results indicate that, while the 4DWW can sustain or enhance operational efficiency and substantially improve work-life balance and stress reduction, these benefits are not uniformly observed across all economic sectors. This paper not only advances the literature on workweek restructuring by clarifying the algorithm for transitioning to a 4DWW but also underscores its potential as a sustainable business practice. The results offer valuable decision-making insights for private companies considering similar transitions, while also highlighting the need for context-specific strategies and policy support—including relevant legislative frameworks in the Baltic region—to ensure successful implementation.