OBJECTIVES: The aim of this study was to calculate the years of working life lost (YWLL) from early exit from work associated with Osteoarthritis (OA). METHODS: We used data from the population-based EpiReumaPt study (Sep2011-Dec2013). 10,661 inhabitants were surveyed to capture all cases of RD within a representative sample of the Portuguese population. We analyzed all aged 50-65 years old (yo), near the official retirement age. YWLL were determined for OA cases with premature exit from work caused by RD (self-reported) estimated as the difference between each participant’s age and the respective age (“observed stock”), while the potential YWLL (PYWLL: YWLL+“expected stock” of YWLL still to occur if there is no return-to-work) was the difference between official and actual retirement ages. We also calculated the percentage of time in inactivity (inactivity ratio=YWLL/Active age-range[15-65yo]). We excluded all OA participants with concomitant inflammatory rheumatic diseases with possible impact on retirement, such as rheumatoid arthritis and spondylarthritis. All cases with retirement prior to onset of OA symptoms were also excluded. All results were based on weighted data. RESULTS: The estimated prevalence of OA in the Portuguese population (50-64 yo) is 29.7% (knee:18.6%; hand:12.6%; hip:3.6%). Among these, 61.8% were out of work versus 47.6% for those without OA (p=0.004), which potentially led to 162,735 YWLL (95 per 1000 inhabitants). Early retirement contributed the most for these YWLL (58%; 94,432 YWLL), followed by unemployment (35%; 57,209 YWLL) and disability pensions (7%; 11,094 YWLL). Women accounted for 80% of these YWLL (153 per 1000 female inhabitants). A total of 161,621 PYWLL were estimated if early retirement is considered and 369,839 PYWLL for all forms of exit from work. The mean YWLL and PYWLL inactivity ratios were 16% and 30%, respectively.  CONCLUSIONS: We estimated a considerable amount of working life years losses associated with OA in Portugal.