Purpose: Eldercare work is characterised by high quantitative work demands and high occurrence of musculoskeletal pain and sickness absence. Our aim was to investigate the association between quantitative demands aggregated at the different organizational levels of eldercare and low back pain (LBP) and sickness absence due to pain among workers. Methods: This study was conducted in 527 eldercare workers from 105 wards across 20 nursing homes in Denmark. We collected workers’ perceived quantitative demands at baseline and workers’ LBP and sickness absence repeatedly over the following year. We aggregated worker-level quantitative demands to the ward and nursing home-levels, and used mixed-effects regression models to investigate the associations between quantitative demands at different organizational levels and LBP and sickness absence over 1 year. Results: Across all models, increased quantitative demands (0–100 scale) at the worker-level was associated with an increased likelihood (OR 1.02) and intensity of LBP (β = 0.01). We did not identify any associations between quantitative demands at the ward-level and either of our outcomes. Across all models, increased quantitative demands at the nursing home-level was associated with increased days with sickness absence due to pain (β = 0.03 to 0.06). Conclusion: In eldercare, workers’ perceived quantitative demands are associated with the presence and intensity of LBP. Further, quantitative demands across the overall nursing home-level are associated with sickness absence due to pain among eldercare workers. These results are of relevance to developing organisational interventions targeting quantitative demands to reduce sickness absence in eldercare.