This paper estimates how much additional work capacity there might be among men and women aged between 55 and 74 in the United Kingdom, given their health, and how this has evolved over the last decade. The objective is not to suggest how much older people should work but rather to shed light on how much ill-health (as opposed to other constraints and preferences) constrains older individuals’ ability to work. We present two alternative methods, both of which rely on constructing a ‘counterfactual’ employment rate for older people based on the behaviour of other similarly healthy individuals. Both methods suggest that there is significant additional capacity to work among older men and women, but that this has been declining over recent years for women (and possibly also for men). This latter finding suggests that the increase in employment rates among older people seen over the last decade are more rapid than would have been expected based on the improvements seen in health alone.