Altice USA is an American cable television provider/multiple system operator with headquarters in New York City, with broadband, pay television, telephony services, Wi-Fi hotspot access, proprietary content and advertising services to approximately 4.9 million residential and business customers in 21 states. The company also provides international news through the February 2017 U.S. launch of i24 NEWS and local news through News 12 Networks.

The company is a subsidiary of Altice NV, a multinational telecoms company. Altice USA is the fourth-largest cable provider in the U.S., which operates under the Optimum and Suddenlink brands, with customers residing in the New York Tri-State area, as well as a number of midwestern and southern states.

In June 2017, Altice USA went public, raising $2.2 billion in its initial public offering. Earlier in 2017, Altice USA announced its intention to rebrand its Suddenlink and Optimum businesses under the Altice name by the end of the second quarter of 2018. Altice USA remains based at Cablevision's former headquarters in Bethpage, New York, which will become the operational center for the company when its main headquarters is moved to One Court Square in Long Island City, Queens.

In November 2016, Altice USA announced a five-year plan for fiber-to-the-home to build a network capable of delivering 10 Gbps broadband speeds. In August 2017, the company stated it was on track to reach one million homes by the end of 2018.

On May 20, 2015, Netherlands-based Altice NV announced that it would enter the U.S. cable market by purchasing Suddenlink Communications, the country’s 7th-largest cable provider, for $9.1 billion. The acquisition closed on December 21, 2015.

On September 17, 2015, Altice NV announced its intention to acquire Cablevision from the Dolan family and other public shareholders for $17.7 billion. The deal was approved by the FCC on May 3, 2016 and after approval from various regional regulators such as New Jersey's Board of Public Utilities and the New York Public Service Commission, closed on June 21, 2016. Under the terms of the deal, Altice paid $34.90 in cash for each share in Cablevision and a 22% premium to the company's stock price; Altice also assumed Cablevision's debt. Prior to this, Altice had already acquired Midwestern cable operator Suddenlink Communications and both companies were subsequently placed under Altice USA.

After the purchase, the Cablevision name was retired, and the company is now known as Altice USA, with Optimum remaining the customer facing brand of the company.

In May 2017, Altice USA announced its intention to rebrand its Suddenlink and Cablevision properties under the Altice name by the end of the second quarter of 2018.

In June 2017, Altice USA went public, raising $2.2 billion in its initial public offering.

Altice engaged in a carriage dispute with the Dolan family (the former owners of Cablevision). Altice's contract to carry AMC Networks group of channels was to expire on December 31, 2016. On December 28 the two sides reached an agreement, three days before their contract with AMC expired.

Altice engaged in a dispute with The Walt Disney Company; the contract to carry the company's channels will expire on October 1, 2017 unless a new agreement is reached.

On October 1, 2017, David Faber of CNBC reported that an agreement in principle had been reached.

– Still in operation, but no longer offers cable or Internet as part of its services