All 11 of the city's gambling houses reported revenue declines. They ranged from 20.9 percent at Resorts Atlantic City to 0.4 percent at Trump Taj Mahal.
Figures released Tuesday by the state Casino Control Commission show table game revenues decreased by 15.6 percent, while slots revenues fell 9.9 percent.
September was the second full month in which casinos in neighboring Pennsylvania offered table games, competing directly with the nation's second-largest gambling market.
Overall, the casinos took in $296.3 million in September, down from $335.4 million in September 2009.