<p>Population ageing has intensified concern over whether frailty-related dependency weakens labour-market participation in later life, especially in middle-income settings where many older adults remain economically active. Thailand is an important case because rapid ageing coexists with continued work at older ages, much of it in informal and physically demanding sectors. This study examines whether frailty-related care needs are associated with labour supply among older adults in Thailand using official province-level statistics. The core inferential dataset is a 2024 ecological cross-section covering all 77 provinces. Three labour-supply outcomes are analysed: employment during the previous 12 months, employment during the previous 7 days, and desire to work. The main explanatory variable is the provincial caregiver-need rate, treated as an indicator of dependency-related frailty. Ordinary least squares models include region indicators and controls for health status, falls, age structure, and Universal Coverage Scheme share, with sensitivity checks using alternative health controls, population weighting, and exclusion of Bangkok. Across specifications, higher caregiver-need rates are consistently associated with lower labour supply among older adults. In the baseline models, a one-percentage-point increase in caregiver needs is associated with a 1.02-percentage-point lower 12-month employment rate, a 0.86-point lower 7-day employment rate, and a 1.02-point lower desire-to-work rate. The results indicate that dependency-related frailty is closely linked to weaker labour-market attachment among older adults in Thailand.</p>