Having an independent exchange rate allows us to compensate for differences in inflation and productivity, and can help boost our economy if we end up in recession. This will enable businesses to sell more widely, achieving greater economies of scale. It will also enable families and businesses to buy from a wider, and so cheaper, range of suppliers. Both of these will boost trade and increase our prosperity. No Most trade barriers were abolished with the creation of the European single market in 1992, and having the same currency will make little extra difference.
Businesses can already buy from suppliers in different countries, and exchange costs are marginal.
We have access to the market, but we avoid the disadvantages of inappropriate interest rates that come with being part of it. In any case, the trade that we pay for in dollars will suffer if we join the euro, because the euro is so volatile against the dollar. In recent years, the Bank of England has proved very successful at controlling inflation. Britain is no longer the high-inflation capital of Europe, but has inflation at a similarly low level to Germany and France. However, if we join the euro we will be forced to use European interest rates, which have generally been much lower than British ones, inevitably leading to an inflationary boom.