Around 700 of the satellites, each of which will weigh less than 150 kg, will be launched into orbit around Earth beginning in 2018. The rest will stay on the ground until replacements are needed.
OneWeb is based in Britain's Channel Islands and has cash from Richard Branson's London-based Virgin Group and chipmaker Qualcomm.
The project will cost between $1.5 billion and $2 billion, OneWeb founder and Chief Executive Officer Greg Wyler said.
Airbus Defense and Space will build the first 10 spacecraft at its Toulouse, France, facility, before shifting production to an undisclosed site in the United States.
Some of OneWeb's satellites will be flown by Branson's space company, Virgin Galactic, which is developing a low-cost, small satellite launcher as well as a suborbital passenger spaceship.
Wyler briefly worked at Google on another project to beam Internet access from space, but left Google in 2014 to work on his own satellite project, named WorldVu, which later became OneWeb.