The British Chambers of Commerce is lobbying for better mobile phone coverage across the UK as part of its new campaign, No More Not Spots.
The BCC campaign is bringing together business communities and network providers to identify challenges and find ways to improve mobile coverage.
A recent BCC poll of over 1,400 companies found that 21% of firms say the UK mobile phone network "doesn't meet their needs in accessing new and existing customers, suppliers and employees".
Despite investment in geographic coverage for voice and text, the BCC says not spots still exist, including in dense commercial centres such as road and rail corridors where access issues, the built environment and the economics of new infrastructure can weaken coverage.
The No More Not Spots campaign is encouraging businesses to report gaps in coverage to the BCC. Scott Roberts, chairman of Polar Technology in Oxfordshire, said: "We can hardly get a signal in the office or factory, and in almost every direction for 20 miles the signal is so weak it drops out during a call. This is destroying our productivity as we rely on mobile phones to communicate and gets things done, especially when our management teams are on the move."
Adam Marshall, BCC director general, said: "A reliable mobile phone signal is one of the most basic requirements for any business, as more and more conversations and transactions take place while people are on the go. Unfortunately, dropped calls and poor signal remains an issue in many areas across the UK.
"Working together, business, communities and operators can identify key gaps in coverage and find shared solutions to resolve the real-world connection problems many business communities face. Our message to all businesses is simple: share and report mobile not spots - so that together we can take action to improve reliable coverage for the future."
The campaign is part of the BCC's focus on "fixing the fundamentals" of the UK business environment to remove barriers to growth.