The boom was revealed by online payments group PayPal, which showed overseas sales at small and medium-sized firms rose by 34 per cent in the second half of 2016.
Sales rose in the first half, too, but by just 10 per cent.
Mark Brant, PayPal's UK managing director, said: 'When the buying power of international shoppers increased, we expected a surge in online exports. But there were other factors.
The best placed firms were those that had already adapted their online stores, for example by letting customers browse in their own language, and pay in their own currency.'
PayPal's data shows that tens of thousands of firms with a turnover of less than £1 million a year sold online to a new country between July and December 2016.
The top five markets were the US, Germany, Australia, France and Italy.
PayPal said customers in all five were attracted to new products exclusive to the UK. There was a 49 per cent a year rise in fashion and sport exports.
Ian Bristow, of outdoor fashion retailer Blackleaf in Lincolnshire, said: 'We feel like we've become a global company over the last six to nine months.'
Source: Vicki Owen - Daily Mail