The Internet & American Life Project at the Pew Research Center said 15 percent of adults do not use the Internet. That figure stood at 30 percent five years ago, the Los Angeles Times reported Monday.
The study found a wide disparity across racial groups that becomes narrower when mobile devices are taken into consideration.
Just over 50 percent of adult Latinos have high speed Internet access at home. Among blacks adults, 64 percent have high-speed Internet service in their homes. Among white, 74 percent of adults have high-speed service at home, the study found.
But many now access the Internet with mobile devices, such as tablets or smartphones.
"Smartphones do offer a potential source of online access to individuals who might otherwise lack the ability to go online at all from within the home, even if that access is somewhat limited in comparison," the report said.
"And indeed, 10 percent of Americans indicate that they do not have a broadband connection at home but that they do own a smartphone," the Internet and American Life Project reported.
The number of dial up subscribers has plummeted in recent years, but the figure has been unchanged for the past two years with 3 percent of adults maintaining a dial-up service, the report found.
In contrast, 46 percent of adults indicated they had broadband at home and a smartphone, while 24 percent indicated they have broadband service at home.
Finally, 20 percent had neither broadband nor a smartphone, the study found.
The survey was conducted April 17 through May 19 by Princeton Survey Research Associate and included 2,252 responses. The results of the survey include a margin of error of 2.5 percentage points.