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Nearly two-thirds of millennials graduated, or will graduate, with student debt, averaging $27,162 per borrower, according to a new report by LendingTree. Despite that hefty student loan burden, newly minted grads are moving to some of the nation's most expensive cities, heavily concentrated in the Northeast, LendingTree found. Boston was one of the most popular cities to live post-college, LendingTree said, followed by Irvine, California, and San Francisco. The states with the highest outstanding college debt per student loan borrower included Washington, D.C., and Maryland.

Particularly with regard to housing expenses, the cost of living in those locations far exceeds the national average. In Boston, for example, the average cost of renting a two-bedroom apartment is $2,821, which means that you would need to earn $120,900 a year just to afford it, according to a separate report by personal-finance site SmartAsset. (To calculate the gross income required, the site set the rent-to-income ratio at 28 percent.) Millennials make $48,146 a year, on average, and pay about $317 a month toward their student loan repayment, according to LendingTree. Those monthly student loan payments amount to more than 11 percent of net income each month. [In this example, monthly take-home pay is $2,808, on average, factoring in federal and state taxes, Social Security, Medicare, insurance costs and a 401(k).] The majority of those polled said that monthly bill affects their spending ability "very much."