The 10 cities with the most and least student debt

Americans collectively hold more student debt than ever before —  a total of over $1.5 trillion.

One reason for this situation is simple: More Americans are choosing to attend college. The Georgetown Center on Education and the Workforce calculates that a bachelor's degree is worth $2.8 million over a lifetime. Earning a degree from an accredited nonprofit college increases lifetime earnings, decreases unemployment and increases life expectancy by at least a decade.

According to a study from loan brokerage company LendingTree, the median balance among student loan borrowers from the 100 largest metropolitan areas ranges from $22,803 to $17,928.

Here are the 10 cities with the most student debt:

Median balance: $20,469
Average number of loans: 3.9
Percentage of borrowers who owe more than $50,000: 24.4 percent
Percentage of borrowers who owe more than $100,000: 7.0 percent

Median balance: $20,560
Average number of loans: 3.9
Percentage of borrowers who owe more than $50,000: 23.3 percent
Percentage of borrowers who owe more than $100,000: 7.9 percent

Median balance: $20,650
Average number of loans: 4
Percentage of borrowers who owe more than $50,000: 24.8 percent
Percentage of borrowers who owe more than $100,000: 8.7 percent

Median balance: $20,679
Average number of loans: 3.6
Percentage of borrowers who owe more than $50,000: 24.2 percent
Percentage of borrowers who owe more than $100,000: 7.7 percent

Median balance: $21,031
Average number of loans: 3.8
Percentage of borrowers who owe more than $50,000: 25.9 percent
Percentage of borrowers who owe more than $100,000: 7.6 percent

Median balance: $21,037
Average number of loans: 3.5
Percentage of borrowers who owe more than $50,000: 23.0 percent
Percentage of borrowers who owe more than $100,000: 6.5 percent

Median balance: $21,357
Average number of loans: 3.7
Percentage of borrowers who owe more than $50,000: 22.9 percent
Percentage of borrowers who owe more than $100,000: 8.7 percent

Median balance: $21,915
Average number of loans: 3.8
Percentage of borrowers who owe more than $50,000: 23.9 percent
Percentage of borrowers who owe more than $100,000: 7.7 percent

Median balance: $22,232
Average number of loans: 3.8
Percentage of borrowers who owe more than $50,000: 26.0 percent
Percentage of borrowers who owe more than $100,000: 9.1 percent

Median balance: $22,803
Average number of loans: 3.4
Percentage of borrowers who owe more than $50,000: 25.8 percent
Percentage of borrowers who owe more than $100,000: 9.8 percent

Here are the 10 cities with the least student debt:

Median balance: $15,273
Average number of loans: 3
Percentage of borrowers who owe more than $50,000: 17.2 percent
Percentage of borrowers who owe more than $100,000: 6.3 percent

Median balance: $15,244
Average number of loans: 3.6
Percentage of borrowers who owe more than $50,000: 20.4 percent
Percentage of borrowers who owe more than $100,000: 5.8 percent

Median balance: $15,244
Average number of loans: 3.3
Percentage of borrowers who owe more than $50,000: 18.3 percent
Percentage of borrowers who owe more than $100,000: 4.8 percent

Median balance: $15,165
Average number of loans: 3.3
Percentage of borrowers who owe more than $50,000: 16.8 percent
Percentage of borrowers who owe more than $100,000: 5.2 percent

Median balance: $15,056
Average number of loans: 3.3
Percentage of borrowers who owe more than $50,000: 16.5 percent
Percentage of borrowers who owe more than $100,000: 3.9 percent

Median balance: $15,025
Average number of loans: 3.1
Percentage of borrowers who owe more than $50,000: 14.0 percent
Percentage of borrowers who owe more than $100,000: 4.0 percent

Median balance: $14,656
Average number of loans: 3.1
Percentage of borrowers who owe more than $50,000: 15.8 percent
Percentage of borrowers who owe more than $100,000: 4.8 percent

Median balance: $14,615
Average number of loans: 2.9
Percentage of borrowers who owe more than $50,000: 14.5 percent
Percentage of borrowers who owe more than $100,000: 4.8 percent

Median balance: $13,808
Average number of loans: 3.1
Percentage of borrowers who owe more than $50,000: 15.9 percent
Percentage of borrowers who owe more than $100,000: 4.4 percent

Median balance: $13,017
Average number of loans: 2.8
Percentage of borrowers who owe more than $50,000: 14.4 percent
Percentage of borrowers who owe more than $100,000: 3.3 percent

Washington D.C. topped the list with the highest median student debt balances. In D.C., nearly 10 percent of borrowers owe more than $100,000. To put that in perspective, the average student loan borrower owes $37,172 when they finish undergrad.

A major reason the nation's capital has such high levels of student debt is because 55.4 percent of D.C. residents have a post-secondary degree, compared to just 34.2 percent across the country. Nearly one in four holds a graduate degree, more than double the national rate of 11.5 percent. This high percentage of citizens with graduate loans is one potential reason why D.C. has so many borrowers with more than $100,000 in debt.

With the exception of Akron, Ohio, all of the cities with the highest levels of debt were in the South. "A combination of factors could be the cause for high levels of median student debt in Southern states," Kevin Walker, Head of Education Loans at LendingTree, told CNBC Make It.

Some possible causes include less parental wealth and support, local schools with smaller scholarship endowments, and lower paying jobs, he explains. A final reason cities south of the Mason-Dixon line are dealing with high student debt levels is because of high attendance at for-profit colleges, which are consistently found to have lower graduation rates and higher loan default rates.

On the other hand, the list of cities with the least amount of student debt was more geographically diverse.

Places like Salt Lake City, Providence and Fresno all made the list of the cities with the least debt. But extremely low student debt levels aren't always a good sign — they can also reflect low college attendance. For instance, McAllen, Texas was found to have the least debt with a median balance of $13,017, but also has below-average educational attainment.

Communities with high and low levels student debt both face serious challenges. In order to make sure you are making a smart investment in your education, be sure to take full advantage of federal student aid, avoid predatory private student loans and consider attending an accredited nonprofit college. 

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