The number and size of free-range laying hen (Gallus gallus domesticus) production systems are increasing within Australia in response to consumer demand for perceived improvement in hen welfare. However, variation in outdoor stocking density has generated consumer dissatisfaction leading to the development of a national information standard on free-range egg labelling by the Australian Consumer Affairs Ministers. The current Australian Model Code of Practice for Domestic Poultry states a guideline of 1500 hens/ha, but no maximum density is set. Radio-frequency identification (RFID) tracking technology was used to measure daily range usage by individual ISA Brown hens housed in six small flocks (150 hens/flock -50% of hens tagged), each with access to one of three outdoor stocking density treatments (two replicates per treatment: 2000, 10 000, 20 000 hens/ha), from 22 to 26, 27 to 31 and 32 to 36 weeks of age. There was some variation in range usage across the sampling periods and by weeks 32 to 36 individual hens from the lowest stocking density on average used the range for longer each day ( P < 0.001), with fewer visits and longer maximum durations per visit ( P < 0.001). Individual hens within all stocking densities varied in the percentage of days they accessed the range with 2% of tagged hens in each treatment never venturing outdoors and a large proportion that accessed the range daily (2000 hens/ha: 80.5%; 10 000 hens/ha: 66.5%; 20 000 hens/ha: 71.4%). On average, 38% to 48% of hens were seen on the range simultaneously and used all available areas of all ranges. These results of experimental-sized flocks have implications for determining optimal outdoor stocking densities for commercial free-range laying hens but further research would be needed to determine the effects of increased range usage on hen welfare.Keywords: laying hen, free-range, stocking density, radio-frequency identification, behaviour Implications Free-range production systems vary in the amount of outdoor space provided per individual hen but few studies have assessed the impacts on range use. Radio-frequency identification (RFID) tracking of hens from ages 22 to 36 weeks showed individuals with more outdoor space per bird (2000 hens/ha), used the range area for longer than hens housed at 10 000 or 20 000 hens/ha. During weeks 27 to 36, hens within the highest stocking density spent the least time outdoors. Outdoor stocking density affected range use which has implications for free-range system management and developing legislative standards that optimise hen welfare.