The number of high-speed Internet lines in the United States increased 34 percent, to 37.9 million lines, last year, the Federal Communications Commission said yesterday, as price wars between Internet service providers made fast connections increasingly affordable.

With phone companies such as SBC Communications Inc. offering cheaper high-speed access, more Internet users are choosing digital subscriber lines, or connections purchased through phone companies, over cable modem service.

"The big increase is probably attributed to the much more aggressive effort by phone companies to offer DSL starting in mid-2004 or late 2003," said Lee Rainie, director of the Pew Internet and American Life Project, a nonprofit that researches the social impact of the Internet.

The number of DSL lines in 2004 went up at a faster rate than the number of cable modem connections, according to the FCC data. DSL high-speed lines rose 45 percent, to 13.8 million lines, in 2004 while cable connections increased by 30 percent, to 21.4 million lines.

The increase in high-speed Internet subscribers has meant tougher competition for providers that used to offer only dial-up Internet, such as Dulles-based America Online Inc. Last month, AOL began offering a high-speed service in the Washington area after losing more than 5 million subscribers in recent years.

Alternative ways of getting a high-speed connection also grew more popular. Satellite or wireless connections increased by 50 percent, to 500,000 connections.