The paper investigates the drivers of farm size and farm size growth in Slovenia during the period 2007-2017 using a farm-level Farm Accountancy Data Network dataset within a quantile regression framework. Farm size growth is measured by growth in utilized agricultural area per farm. The findings suggest that growth in farm land size is driven by initial farm land size and policy subsidy support. Contrary to expectations, human capital does not play an important role in either farm land size or farm land size growth according to quantile regressions. These findings from inter-quantile comparative analysis are important for farm-related structural and rural development policy.