Sprint says it will pay $2.97 per share for Clearwire stock it doesn't already own. Last week, the company said it would offer $2.90 per share, which totaled $2.1 billion.
The deal still needs the approval of regulators and Clearwire shareholders, but Sprint expects it to close by the middle of next year. The acquisition will give Sprint total control of the struggling Clearwire and more space on the airwaves for data services.
Sprint Nextel Corp. is the country's No. 3 wireless carrier, trailing Verizon Wireless and AT&T.
Clearwire shares fell 25 cents, or 7 percent, to $3.12 in premarket trading.