While the national debate rages over immigration, new research shows how much new immigrants cost state and local governments in the short-term -- and how much they pay off in the long-term.

Two studies, one by the Urban Institute and a larger one by the National Academies of Science (NAS), find that first-generation immigrants are costlier to state and local governments than native-born adults, but over time, those effects reverse. While first-generation immigrants cost an average of nearly $3,000 more per adult, the adult children of these immigrants eventually catch up and contribute the most on average to federal, state and local coffers.

Kim Reuben, a senior fellow at the Urban Institute, says the initial higher costs of new immigrants is in large part because of their children. "Education is expensive -- if you have more kids in general as a group compared to other groups, you're going to have higher costs," says Reuben, who co-authored the study and contributed to the NAS report. "But the answer isn't to not educate those kids because we also find that the people who contribute the most to society, even when you control for demographics, are these immigrant [kids]."