Education policy in England has explicitly aimed to remodel state schools in the image of independent, private, schools. However, the body of research evidence on the operation of private schools is very small. Critics have frequently argued that, in contrast to state schools, private schools use resources efficiently because their autonomy gives them freedom to make efficient choices in response to market pressures. We investigated the resource allocation decisions of income private schools using data from their financial accounts. We report the associations of private school spending and performance and teacher and non-teacher numbers, teacher salaries and regional earnings. Schools with higher fees had more teachers and non-teachers per pupil, but similar average staff wages to schools with lower income. Yet we found little evidence that achievement was associated with resource use in English private schools. That is, we found no evidence to support the view that financial autonomy enabled flexibility in using resources to promote higher achievement.