The government must take action to avoid two-tier broadband access in rural and urban areas, said the Federation of Small Businesses (FSB).
The government had yet to make it clear how it would ensure a seamless broadband infrastructure to avoid a divide between town and country
Many small businesses broadband speeds are inadequate, according to the recent CMA Internet Opportunity Survey, suppored by the FSB.
Poor or nonexistent broadband connections were hampering productivity and the ability of businesses to grow.
Some 9% of businesses cannot access broadband at all, and 22% cannot access current generation broadband at least one of their sites.
For the 84% with broadband, there was a marked difference in the typical speeds they received.
But more than a quarter could only just obtain speeds considered by Government to be a minimum level of service – 2Mbps.
FAB chairman John Walker said a fast, reliable broadband service was crucial for breaking down barriers to business.
Access to broadband allowed small firms to expand into new markets and allowed staff to work flexibly.
"We are concerned that the divide that currently splits urban and rural areas in terms of their broadband access, will not be resolved by the government's existing commitments.
The government should sets out a clear commitment and details on how it will deploy superfast broadband across the country up to and beyond 2015.
It should ensure that businesses in all parts of the country were able to compete on a level playing field.
"We must ensure all small firms have the best opportunity available to them to grow, innovate and take on staff," said Mr Walker.
"Good broadband access, connection and speeds are central to that."
The government has pledged to ensure universal broadband coverage and superfast broadband coverage for 90% of the population in each local authority by 2015.
Local authorities should work with their small business communities to develop local broadband plans that reflect the needs of local businesses, said Mr Walker.