"It was unexpected," said Bettencourt, who said he received a phone call from the state earlier in the day. "The city did not solicit, or apply for this. There is still some information I need to find out, in order to find out if this will work well for our city."
A Gateway city typically is a small-to-midsize community, lagging state average for income and education, as determined by a five-year review of data, the state said.
In 2010, 24 Massachusetts cities, including Lynn, Malden, and Salem, were selected. On Monday, Peabody and Attleboro were added, boosting the total number to 26, according to the state.
Gateway cities are eligible for state grants for housing, transportation, business development and other public services, the state said.
"Our Gateway cities possess tremendous potential and opportunities," Greg Bialecki, the state Secretary of Housing and Economic Development, said in a statement. "By continuing to invest . . . in these communities, we are creating new opportunities for growth in the future."
Bettencourt said he plans to meet with a state official on Thursday to learn more about the designation. "It could put us in a smaller pool of applicants, for some very valuable grants," he said. "But until we know more about how it works, it's too early to say" what impact it will have.
Gateway cities must meet three criteria: a population of 35,000 to 250,000; less than 38.7 percent of adults hold a bachelor's degree; and the median household income is below $65,981, the state average.
Peabody has a population of 50,824, and 30 percent of adults have a bachelor's degree or higher. The median household income is $65,471, according to the state.
Peabody was added to the list, when its average household income dropped below the state average, a state spokesman said.
"Every year, we go back and look at the numbers to see if anybody new should be added," said Jason Lefferts, spokesman for the Executive Office of Housing and Economic Development. "We select them purely by the numbers."