Nearly 7 percent of Sonoma County households earn more than $190,000 a year, placing them among the top 5 percent of income earners nationally.
While that's a lot more than many counties in Kentucky, Missouri, Montana and Idaho, it pales in comparison to the rest of the Bay Area.
Take Marin County, where nearly 19 percent of all households are in the national top 5 percent, or San Mateo and Santa Clara counties, where more than 16 percent of households are among the 5 percent.
Only Solano County, at 6.18 percent, has a lower share of its households meeting the threshold, according to a recent report by the U.S. Census Bureau.
The report, which is based on five years of surveys from the American community survey from 2007 to 2011, showed that most upper-income households lived in high population counties, particularly along the nation's coasts.
In California for example, counties with the highest concentration of upper-income households run contiguously from Sonoma County all the way down to San Diego County. North of Sonoma County, the statistics take a precipitous fall.
"In many ways we're more like the Greater Bay Area than we are like Del Norte or Humboldt," said Ben Stone, executive director of the Economic Development Board.
Of the nine counties in the Bay Area, Stone said Sonoma County shares more in common economically with Napa and Solano. In Napa County, just over 9 percent of households are considered upper-income by national standards.
In Lake and Mendocino counties, only 1.98 and 2.39 percent of households, respectively, are considered among the upper-income level.
Stone and Jonathan Coe, president and CEO of the Santa Rosa Chamber of Commerce, said the data are signs of opportunity for businesses and entrepreneurs considering locating in Sonoma County. Combined with high levels of educational attainment among the local population, Sonoma County is a far more affordable place to do business than elsewhere in the Bay Area, Coe said.