U.S. cable company Charter Communications (CHTR.O) said on Thursday it was buying Cablevision's CVC.N rural cable asset Optimum West for $1.63 billion.
Charter said it expected the deal to close in the third quarter of this year.
Optimum West, which offers cable, Internet and telephone services in Colorado, Montana, Wyoming and Utah to around 366,000 customers, was one of the fastest-growing cable assets in the United States, Charter said.
Cablevision had said in November it was looking to sell the unit, which it bought for $1.4 billion in 2010, after it had received inquiries about the business.
Citi and JPMorgan were co-lead financial advisers to Cablevision on the deal. Credit Suisse and Goldman Sachs acted as financial advisers to Charter.
BofA Merrill Lynch and Guggenheim Securities also provided financial advice to Cablevision. Sullivan & Cromwell LLP acted as legal counsel to Cablevision.
(Reporting by Nicola Leske in New York; Editing by Dale Hudson)