The result was an improvement from last year, when the FCC found that 26 million Americans lacked access to high-speed Internet connections. The 2012 report also noted significant progress in the deployment of high-speed 4G cellular networks.
"The U.S. has now regained global leadership in key areas of the broadband economy, including mobile, where we lead in mobile apps and 4G deployment; but, in this flat, competitive global economy, we need to keep driving toward faster broadband and universal access," FCC Chairman Julius Genachowski said in a statement.
Expanding Internet access has been a top priority for the FCC under Genachowski, who argues that broadband is the great infrastructure challenge of the 21st century.
Last year, the commission converted a $4.5 billion fund for rural telephone service into a subsidy for expanding broadband access. But the report noted that implementation of the new Internet subsidy has only just begun.
About 14.5 million of the 19 million people without broadband access live in rural areas, the report found. Additionally, only about 40 percent of Americans who could purchase broadband do so, citing cost, lack of technical skills or the perception that the Internet is not relevant or useful for them.
The commission applauded companies for investing about $1 trillion since 1996 in wireline and wireless broadband, according to industry statistics.
The two Republican commissioners, Ajit Pai and Robert McDowell, dissented from the commission's finding that the pace of deployment is inadequate.
McDowell accused the three Democratic commissioners of using the report as pretext to justify more regulation.
"In reality, the growth of broadband deployment in America, especially regarding the mobile marketplace, has been swift and strong," McDowell said.
Pai argued that the commission should have counted people who are covered by high-speed cellular service as having broadband access. Under that definition, just 5.5 million would lack access to any broadband service, according to Pai.