Background Suicide is one of the leading causes of premature mortality worldwide. Few studies have assessed long-term trends or sex differences in its incidence over time. We have investigated the age-, sex- and method-specific trends in suicide in England and Wales from 1861 to 2007. Methods Overall age-standardized suicide rates using the European Standard Population and age-, sex- and method-specific rates were calculated for ages ≥15 years from 1861 to 2007. Results Rates in males were consistently higher than females throughout the 19th and 20th centuries, although the male-to-female sex ratio fluctuated from 4 : 1 in the 1880s to 1.5 : 1 in the 1960s. Suicide rates increased in all age groups in the 1930s, coinciding with the Great Depression. The highest male rates (30.3 per 100 000) were recorded in 1905 and 1934 and have since been declining. Female rates peaked in the 1960s (11.8 per 100 000), declining afterwards. In both sexes the lowest recorded rates were in the 21st century. There was a rapid rise in the use of domestic gas as a method of suicide in both sexes following its introduction at the end of the 19th century. There was no evidence that this rise was accompanied by a decline in the use of other methods. Self-poisoning also increased in popularity from the 1860s (5% of suicides) to the 1990s (22% of suicides). Conclusions The epidemiology of suicide in England and Wales has changed markedly over the past 146 years. The rapid rise in gas suicide deaths in the 1920s highlights how quickly a new method of suicide can be established in a population when it is easily available. The increase in suicides during the Great Depression has implications in relation to the current economic crisis. Changes in the acceptability and lethality of various suicide methods may account for the large variations in sex ratios over time.