That investment was announced last August, but the procurement process involved is only just getting under way now.
The aim of the project is to build masts in areas with no existing 4G mobile connectivity, and up to 70 sites are set to benefit over its lifetime.
Scottish National Party South Scotland regional list MSP Paul Wheelhouse has welcomed the inclusion of the Borders on the list of sites in line for better communications links.
“I’m delighted to see the Ettrick Valley chosen as one of the first sites to benefit from the 4G infill project,” said Mr Wheelhouse, also business minister at Holyrood.
“We’ve already taken steps to improve broadband connections with £400m invested by the Scottish Government in the initial Digital Scotland Broadband rollout, and a further £600m being invested through our Reaching 100% programme, ensuring that every premises in Scotland can access superfast broadband with speeds of 30 mbps by 2021.
“But mobile coverage is equally important, if not more so, particularly to small isolated communities.
“I’m very hopeful that this investment will make a difference to people in Ettrick Valley, and I hope that, should it be successful, other communities in the south of Scotland might be able to benefit from it in future.”
Fellow cabinet minister Fergus Ewing, secretary for connectivity, added: “Widespread high-speed and reliable mobile coverage is just as vital as broadband and ensures that people, communities and businesses are able to stay connected.
“Improving mobile coverage across Scotland is key to achieving our ambition to become fully digitally connected.
“The infill programme will target the areas where it can make the most difference, achieving better and cost-effective connectivity.”