Comcast is buying Time Warner Cable for $45.2 billion in a deal expected to close by the end of the year.
Charter spokesman Alex Dudley says Charter will then buy 1.4 million Time Warner subscribers from Comcast for an estimated $7.3 billion.
Charter also will buy one-third of a spin-off company Comcast is creating to service 2.5 million Comcast customers. That deal is worth an estimated $2.1 billion.
Charter and Comcast also will exchange about 1.6 million customers.
Comcast spokesman John Demming says the changes will primarily affect customers in the Green Bay and Milwaukee markets.
Dudley says customers should find the transition from one provider to another seamless.