The Big Bang was the deregulation of the London Stock Exchange on 27 October 1986. It ended fixed commissions and the split between brokers and jobbers, let ba…
Geoffrey Howe abolished exchange controls. British funds could buy foreign shares freely, exposing how small London's broking firms were.
The government dropped a court case against the Stock Exchange's rule book. In return, fixed commissions would end by late 1986.
The limit on outside ownership of member firms rose from 29.9% to 100%. Barclays, Warburg, Citicorp and UBS bought famous names.
Fixed commissions ended, brokers and jobbers could combine, and stamp duty on shares was halved to 0.5%.
SEAQ went down on the first morning. Within weeks, three-quarters of business had left the floor; by December about 95%.
The Act made unauthorised investment business a crime and set up the Securities and Investments Board over self-regulating bodies.
The FTSE 100 fell 10.8% on Monday and 12.2% on Tuesday. The crash was global, but it tested London's new market makers.
Only eight UK listings in nine months of 2026. Chancellor John Healey's first Budget falls the day after the anniversary.
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