There were 3.08 million landlines in Michigan in 2012, the most recent year available, according to the report conducted by the Michigan Public Service Commission. That's down 8 percent from 3.34 million in 2011.
The landline total has fallen steadily since peaking at 7.01 million in 2001.
The commission conducts the yearly study to examine competition among landline providers. The commission lacks jurisdiction over cellphones, but says there were 9.25 million wireless subscribers in Michigan at the end of 2011.
"The telecommunications industry in Michigan continues to experience the same technological changes as the rest of the nation," the report says. "Incumbent providers have continued to experience a decrease in their traditional wireline customer lines, a trend that began in the year 2002."
AT&T had 52 percent of the Michigan landline market in 2012, the report said. Frontier had 10.6 percent and other carriers the rest.