United Kingdom and the euro

The United Kingdom, an EU member state, has not replaced its currency, the pound sterling with the common euro currency. The pound sterling does not participate in the European Exchange Rate Mechanism, a prerequisite for euro adoption. The UK negotiated an opt-out from the part of the Maastricht Treaty of 1992 that would have required it to adopt the common currency, and the Conservative-Liberal Democrat coalition government that was elected in May 2010 pledged not to adopt the euro as its currency for the lifetime of the parliament. Polls have shown that the majority of British people are against adopting the euro. In a June 2016 referendum the UK voted to withdraw from the European Union, which when enacted will eliminate any future discussion of it adopting the euro.

The United Kingdom entered the European Exchange Rate Mechanism, a prerequisite for adopting the euro, in October 1990. The UK spent over £6 billion trying to keep its currency, the pound sterling, within the narrow limits prescribed by ERM, but was forced to exit the programme within two years after the pound sterling came under major pressure from currency speculators. The ensuing crash of 16 September 1992 was subsequently dubbed "Black Wednesday". During the negotiations of the Maastricht Treaty of 1992 the UK secured an opt-out from adopting the euro.

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