There is a profusion of evidence on the population and supply side factors explaining demand for emergency care, but surprisingly very little evidence about how seasonal patterns of demand vary across regions. Such information is crucial to help hospitals manage fluctuations in demand and ease capacity constraints. The objective of this study is to analyse the patterns of weekly attendances to Accident and Emergency departments in England, controlling for a wide range of determinants. The study uses both panel and common trend methods on data for 135 English hospitals and their catchment areas merged from a variety of sources over 156 weeks from 2012 to 2015. Modelling of unobservable factors with common trend models shows systematic patterns in the data related to season and the location of providers. Coastal areas experience more attendances in summer than urban areas, and this trend is reversed in winter, possibly due to temporary population movements. Internal reorganizations between major A&E departments and minor injury units within hospitals lead to structural breaks in attendances. In the panel models, only the share of the working population, weather and socioeconomic deprivation are statistically significant predictors of attendances in the panel models. The forecasting ability of both panel and common trends methods is similar. Fine-tuning funding allocations across trusts and seasons according to temporary population movements could be a promising avenue to help alleviate existing capacity constraints emergency departments.