From 2017, each Autumn the Chancellor of the Exchequer publishes an Autumn Budget statement which details the plans for Government funding and spending intentions based on the economy of the United Kingdom over the upcoming year. Before 2017 the budget was released only in the Spring, which has now become the Spring Statement. The Autumn Budget can also contain information on planned changes to tax collection and taxation rules which would affect the country in the upcoming year, whether they affect companies or self-assessment individuals. Usually these tax changes are announced a year before implementation to allow for software providers and users to update their systems.
The intended date for the 2019 delivery was the 6th November 2019. Boris Johnson, the Prime Minister, wants a general election to be held on the 12 December 2019 which would require a dissolution of Parliament 25 working days before this date. To achieve this, Parliament would need to dissolve on the 6th November itself. Therefore, the Budget Statement for Autumn 2019 has been cancelled.