The government must ensure that all UK companies have access to adequate broadband services, it has been claimed.
In a new report, the Federation of Small Businesses (FSB) claims that online trade is vital for growth, and UK firms must be given access to the web.
The FSB said the internet helps to shrink borders and is "an important tool" for small businesses to find new customers in other countries.
It claimed that a key barrier to UK companies exporting is a lack of access to high-speed downloads.
For nine per cent of small firms, current generation broadband – up to 24Mb – is not available across any of their sites and 22 per cent said it is not available on at least one.
And around a quarter of small businesses only have access to speeds of up to 2Mb – acting as a major barrier to trading online.
The FSB is concerned that the government is not doing enough to ensure that the UK has a seamless broadband infrastructure - one which avoids a divide between rural and urban areas.
John Walker, national chairman of the FSB, said online trading has helped empower small businesses to find new markets, sell new products, try new models and compete on an equal footing with larger businesses.
"Online trade has great potentials for small businesses but it still has its barriers. These must be removed," he stated.
"The biggest obstacle for many small businesses is the lack of broadband speeds and so as a result they cannot compete online."
Mr Walker called on the government to ensure all small businesses are connected and have access to the broadband speeds they need to allow firms to sell goods over the internet.