Background: In developed countries, children’s independent mobility levels are low. Built environmental factors and parental safety concerns are well-known to predict the level of independent mobility adults grant to children. In contrast, the influence of adults’ socio-demographic characteristics and neighbourhood social cohesion on children’s independent mobility is largely unexplored. This study investigated the influence of adults’ socio-demographic factors and neighbourhood social cohesion on distances they would permit children for independent travel and outdoor play. Methods: In 2013, a random sample of 1293 Australian adults (mean age: 56.1 years, 52 % male, 81 % parents) participated in the Queensland Social Survey (QSS) via computer-assisted telephone interview. Socio-demographic factors measured included age, sex, parental status, education and area-level socio-economic disadvantage. Perceived neighbourhood social cohesion was assessed using a standardised scale. Adults reported the distances children aged 8–12 years should be allowed to walk/cycle to places, and play outdoors without adults. Responses were categorised into ‘within sight’, 1 km. Ordinal logistic regression was used to assess associations of socio-demographic factors and neighbourhood social cohesion with distances adults would permit for children’s independent travel and outdoor play. Results: Parents and adults with lower education were less likely to permit greater distances for children’s independent travel (OR = 0.57 and OR = 0.59, respectively). Women, parents and adults with lower education were less likely to grant children greater distances for independent outdoor play (OR = 0.61, OR = 0.50 and OR = 0.60, respectively). In contrast, adults with higher perceptions of neighbourhood social cohesion were more likely to permit children greater distances for independent travel (OR = 1.05)and outdoor play (OR = 1.05). Adult age and area-level socio-economic disadvantage were not associated with distances adults would permit for independent travel and outdoor play. Conclusions: Women, parents (particularly those of younger children), adults with lower education and those who perceived neighbourhood social cohesion as being lower were less willing to let children independently travel further away from home. Interventions to increase children’s independent mobility may be more effective if targeted to these groups. In addition, increasing neighbourhood social cohesion may help increase adults’ willingness to grant children greater independent mobility.