Wire One is currently based in Denver, Colorado and employs over 350 people in the US and Europe.
BT aims to use the acquisition to expand its existing videoconferencing capabilities and services offering to its customers.
"The acquisition of Wire One is a tremendous addition to BT's global managed video capabilities, the fastest growing sector in the teleconferencing industry," said Aaron McCormack, chief executive officer of BT Conferencing.
"We look forward to using these capabilities to create a new suite of managed video services on our global IP network and providing an enhanced offering to both BT Conferencing and Wire One's existing and future customers."
According to analyst firm Wainhouse, the videoconferencing market generated revenues of $140m in 2007 and is forecast to be worth $2.6bn by 2010.
"Wire One customers will see significant benefits from BT's extensive global presence and a compelling managed services offering," added Dan Connors, chief executive officer of Wire One.
BT is acquiring Wire One from The Gores Group LLC and the proposed acquisition is dependent on all the usual regulatory clearances being met.
Exact financial details of the sale were not disclosed but the audited gross assets of Wire One as at end of 2007 were set at $90.5m.