This paper presents an approach to assessing presenteeism (on-the-job productivity loss) that is related to perceived work ability. The aim of this explorative research was to find out if perceived work ability could be a robust indicator, interchangeable with presenteeism, in Finnish food industry organizations. The developed approach was based on existing presenteeism research as well as on register and survey data. The approach demonstrates that one step downward on the 10-point perceived work ability scale theoretically reduces employees' on-the-job productivity by ˜5 percentage points. At the company level, on-the-job productivity loss was 3.7% (mdn 0), while sickness absence was 5.0% (mdn 2.2). The probability of productivity loss among factory workers was fourfold compared to women in office work. The developed approach makes it possible to assess perceived productivity loss at the level of an individual and an organization. Perceived work ability may, in fact, be a robust indicator for assessing perceived productivity loss.