Viacom, which owns MTV, BET, Comedy Central and Nickelodeon, among other networks, has begun informing its Charter-subscribing viewers that its channels won't be available after Sunday if a renewal agreement with their cable operator isn't reached.
"Despite our efforts, Charter continues to insist on unreasonable and extreme terms that are totally inconsistent with the market", Viacom said in its statement.
A person familiar with the situation told Reuters that the current agreement between Charter and Viacom will expire October 15. A blackout would hit 16.5 million subscribers.
Charter spokesman Joe Durkin declined to comment.
Earlier this year, Charter moved Viacom's flagship networks to its most expensive programming tier, a move that threatened the media company's affiliate and advertising revenue.
Viacom CEO Bob Bakish has accused Charter Communications of attempting to stifle the development of low-priced virtual MVPD services. Bakish has made it a priority to improve relations with distributors.
The impasse with Charter comes at an unfortunate time for Viacom, which had been set to report its first annual sales growth since its ratings fortunes took a dramatic downward turn in 2011.
Shares of Viacom were marginally down in extended trading, while Charter shares were unaffected.