Our study on a sample of Estonian creative knowledge employees indicates considerable disparities between their actual, contractually agreed, and desired amounts of working time. Nearly two thirds of the employees studied exhibited a mismatch between their desired and contractual working schedules, reflecting the constraints that employment contracts set on preferred working time. Our study results reveal that even if the employees had access to flexible working time options, a majority of them still followed roughly the standard nine-to-five working schedule even though their desired timing of work may have been different. This may be driven by various social norms and family commitments that warrant further study. The actual duration of the working day is longer than contractually agreed for 90 percent of the employees studied, which may pose health risks to employees. Our ordinary least squares (OLS) regression estimates show that the more educated the employee is, the less overtime work they did, while the higher their salary level, the more hours of overtime the employee did. The OLS regression estimates for the time difference between the actual start and the contractual start of the working day show that women tended to start their working day later and men earlier than officially required. Interestingly, the larger the family the employee had, the more the actual start time of work shifted to being earlier than contractually required. The older the employee, the later the start of their working day was from the official schedule. Our study highlights potentially large inefficiencies in industrial relations and in the use of the potential of employees in creative knowledge work that may have considerable adverse effects on the financial results of companies and on socio-economic development in general.