Daily Junction.mobi portalNews · January 21, 2025 · Sarah Mitchell · 8 min
On 27 October 1986, the London Stock Exchange underwent the most radical deregulation in its history. Fixed commissions were abolished, electronic trading replaced face-to-face dealing, and foreign banks flooded into the City. The Big Bang transformed London into a global financial centre, created vast wealth, but also sowed the seeds of the 2008 financial crisis.
On 27 October 1986, the London Stock Exchange underwent the most radical transformation in its 200-year history. In a single day — known as the Big Bang — fixed commissions on stock trades were abolished, the separation between brokers and jobbers ended, and electronic trading replaced face-to-face dealing on the trading floor. Foreign banks were allowed to buy British stockbroking firms, and a wave of takeovers swept away the old City partnerships. The reforms were driven by Margaret Thatcher's determination to modernise the City of London and prevent financial business moving to New York and Tokyo. The Big Bang succeeded spectacularly: London became the dominant financial centre in Europe and one of the top three globally. Financial services employment exploded from 300,000 in 1986 to over 1 million by 2008. Vast wealth was created, and the City became a symbol of Thatcherite capitalism. But the Big Bang also encouraged risk-taking, leverage, and light-touch regulation that contributed to the 2008 financial crisis. The reforms transformed Britain's economy and society, for better and worse, and their legacy remains fiercely contested.
To understand the Big Bang, you must understand the old City of London — the financial district that existed before 1986. The City was governed by restrictive practices dating back centuries:
Stockbrokers charged fixed commissions on trades, set by the Stock Exchange. There was no price competition, and large institutional investors — pension funds, insurance companies — paid the same rates as small private investors. This made London expensive and uncompetitive.
The Stock Exchange operated on a system of single capacity: brokers (who dealt with clients) and jobbers (who made markets in shares) were separate and could not perform each other's functions. This was intended to prevent conflicts of interest but created inefficiency and higher costs.
Stock Exchange member firms could not be owned by outsiders, particularly foreign banks. The City was dominated by small British partnerships, often family firms, with limited capital and global reach.
Trading took place on the Stock Exchange floor, where jobbers and brokers met face-to-face to negotiate deals. There was no electronic trading, and the system was slow and labour-intensive.
This system was defended as ensuring integrity and stability, but by the 1980s it was increasingly seen as outdated and anti-competitive. Business was moving to New York and Tokyo, where commissions were lower and technology more advanced.
By the early 1980s, pressure for reform was mounting:
New York and Tokyo had deregulated their financial markets and were attracting business away from London. The New York Stock Exchange had abolished fixed commissions in 1975, and Tokyo was rapidly modernising. London risked becoming a backwater.
Electronic trading was making face-to-face dealing obsolete. Computers could match buyers and sellers instantly, reducing costs and increasing speed. The Stock Exchange's reliance on the trading floor was increasingly anachronistic.
Large institutional investors — pension funds and insurance companies — were demanding lower commissions. They argued that fixed commissions were a cartel that inflated costs and reduced returns for savers.
The Thatcher government was ideologically committed to deregulation and competition. In 1983, the government threatened to refer the Stock Exchange to the Restrictive Practices Court unless it agreed to reform. The Stock Exchange, facing legal defeat, agreed to negotiate.
The Big Bang was not a single reform but a package of changes implemented simultaneously on 27 October 1986:
Fixed commissions were abolished, and brokers were free to compete on price. This led to a collapse in commission rates, particularly for large institutional trades. Small investors saw little benefit, but pension funds and insurance companies saved billions.
The separation between brokers and jobbers was abolished. Firms could now act as both brokers (dealing with clients) and market makers (trading on their own account). This created potential conflicts of interest but increased efficiency and reduced costs.
Foreign banks were allowed to buy Stock Exchange member firms. This led to a wave of takeovers as American and European banks bought up British stockbroking and jobbing firms. Traditional City partnerships were swept away, replaced by global investment banks.
The Stock Exchange introduced SEAQ (Stock Exchange Automated Quotations), an electronic system that replaced face-to-face trading. Dealers now traded via computer screens, and the trading floor became obsolete.
The immediate impact of the Big Bang was dramatic:
In the months before and after the Big Bang, foreign banks bought up British stockbroking and jobbing firms:
The old City partnerships, with their limited capital and family ownership, could not compete. Many sold out for vast sums, creating a generation of City millionaires who retired to the country.
The Stock Exchange trading floor, once the heart of the City, became redundant. By 1991, it was closed. Trading now took place via computer screens in dealing rooms across the City.
Deregulation led to an explosion in City salaries and bonuses. American investment banks brought their pay culture to London, offering seven-figure packages to top traders and bankers. The City became a magnet for ambitious graduates, and the culture shifted from gentlemanly restraint to aggressive deal-making.
The long-term impact of the Big Bang was profound:
The Big Bang cemented London's position as Europe's dominant financial centre. By 2008, London handled:
London overtook Frankfurt, Paris, and Zurich, and rivalled New York and Tokyo. The City became the engine of the British economy, contributing over 10% of GDP.
Financial services employment exploded from 300,000 in 1986 to over 1 million by 2008. The City created vast wealth, not just for bankers but for lawyers, accountants, consultants, and support services. London property prices soared, driven by City bonuses.
The Big Bang contributed to rising inequality. City salaries and bonuses far outstripped wages in other sectors, creating a two-tier economy. By 2008, the top 1% of earners — many in finance — took home 15% of national income, up from 6% in 1979.
Deregulation encouraged risk-taking and leverage. Investment banks, now allowed to trade on their own account, took bigger bets with borrowed money. Complex financial products — derivatives, mortgage-backed securities — proliferated. The culture shifted from conservative relationship banking to aggressive proprietary trading.
The Big Bang was accompanied by a shift to light-touch regulation. The old self-regulatory system was replaced by the Securities and Investments Board (SIB), later the Financial Services Authority (FSA). But the FSA was criticised for being too close to the industry and failing to prevent excessive risk-taking.
The Big Bang's legacy was tested in the 2008 financial crisis. British banks, particularly Royal Bank of Scotland (RBS) and HBOS, had taken excessive risks in mortgage-backed securities and derivatives. When the US housing market collapsed, British banks faced collapse.
The government was forced to bail out the banks with £137 billion of taxpayer money, the largest state intervention in the economy since the Second World War. RBS and HBOS were effectively nationalised, and the City's reputation was shattered.
Critics argued that the Big Bang had created the conditions for the crisis:
Defenders argued that the crisis was caused by global factors — US subprime mortgages, Chinese savings gluts — not the Big Bang. But the political damage was done. The City, once celebrated as a Thatcherite success story, was now blamed for economic disaster.
The Big Bang's legacy remains contested:
Supporters argue the Big Bang was essential to modernise the City and prevent business moving abroad. It created jobs, wealth, and tax revenue, and made London a global financial centre. Without the Big Bang, London would have declined like other European financial centres.
Critics argue the Big Bang prioritised short-term profit over long-term stability. It encouraged risk-taking, inequality, and a culture of greed. The 2008 crisis showed the dangers of light-touch regulation and excessive leverage. The Big Bang enriched bankers but left taxpayers to pick up the bill when it went wrong.
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