The purpose of this paper is to explore the patterns and variation in informal caregiving between 2001 and 2011 in England. We use small area data (MSOA) from the 2001 and 2011 English censuses to capture provision of informal care and intensity of care (number of hours). The analysis further uses local authority level social care provision variables and a range of control variables at local level; such as age structure, health, deprivation, income, and employment. We consider both supply side factors such as employment of caregivers and family relations, and demand side factors such as need and availability of substitutes. The provision of informal care has increased over the period, while formal care through local authorities has decreased. We hypothesise that this is due to a substitution between formal and informal care as well as to changes in broader socio-economic conditions over the period considered. The relation is estimated through instrumental variable models, in order to control for the potential endogeneity of formal to informal care. We find that the increase in informal care is most notable for care of medium to high intensity (carers providing more than 20 hours of care per week). It is also for this level of intensity we find a substitution effect between informal and formal care, indicating that informal care covers for a loss in formal care services.