Netflix has registered its opposition to the proposed Comcast and Time Warner Cable (TWC) merger in a letter to shareholders available online.
Citing the decline of digital subscriber line (DSL) in the US in favour of cable internet, Netflix is worried that Comcast could soon control the majority of high-speed broadband connections in America.
"The combined company would possess even more anti-competitive leverage to charge arbitrary interconnection tolls for access to their customers," the streaming service said. "For this reason, Netflix opposes this merger."
Outlining its finances and membership for the last financial year, Netflix now has a membership of more than 48 million and took profits of $53m (£32m) in the first quarter of this year.
The company is also planning to raise its fees for new members by one or two dollars depending on the country, but will freeze prices for existing members "for a generous time period".
Last weekend the Financial Times reported that Comcast and TWC had entered negotiations to sell cable assets worth $20bn (£12bn) to Charter Communications, "according to people familiar with the matter".
The move was interpreted by the FT as intending to "allay Washington’s concerns about the proposed merger", and was said to affect up to 5 million subscribers.
