The average college graduate leaves school with tens of thousands of dollars in debt. It's unlikely that many of these borrowers could have paid for their education without taking on any debt. But many will have taken on more than necessary because they made one or more of the following errors.

College students rushing on a stairway.

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1. Borrowing more than they needed to

Many students end up taking out more student loans than they needed to because they didn't exhaust all of their other options first. Try applying for financial aid, grants, and scholarships before you turn to student loans. You should also look for other ways to reduce how much your school costs, like working while you're in school or living in a more affordable place. 

If you do end up borrowing more than necessary, resist the temptation to spend that extra money on items on your want list. Pay it back to your loan servicer to reduce your outstanding balance. This will also limit the amount you must pay back in interest over time.

2. Not making interest payments while in school

Subsidized federal student loans won't accrue interest while you're in school because the government pays any interest that these loans accumulate while in deferment. But this isn't the case for unsubsidized federal student loans or private student loans. They might not require you to make payments while you're still in school, but your balance will continue to accrue interest the whole time. If you don't make any payments while in school, you'll end up graduating with a larger balance than anticipated.

Try to pay at least enough to cover the interest charges while in school. You might have to seek out a part-time job, but it'll be worth it in the long run because when you leave school, you'll only have to pay back the initial amount you borrowed.

3. Using deferment and forbearance unnecessarily

Federal student loan servicers enable you to place your loan in deferment if you're unable to make payments due to still being in school, economic hardship, active military service, disability, or other reasons. Forbearance works in a similar way to deferment, but it's up to your lender or loan servicer to decide if you qualify for this. 

Deferment and forbearance are useful tools that can help keep you out of default, but don't use them unnecessarily. Your loans may continue to accrue interest while in deferment or forbearance, so you'll end up with a larger balance to pay back in the end. You're also limited in the number of times you can claim deferment or forbearance, so if you use it for no reason, you might not be able to use it when you really need it down the line.

4. Consolidating loans unnecessarily

When you consolidate a loan, you're taking out a new student loan to replace your old ones. Many borrowers like this because then they only have a single student loan payment to worry about instead of several. But what many don't realize is any interest the old loan had accrued becomes part of the principal on the new consolidated loan. That means you'll be earning interest on a larger balance, so the amount you owe could swell more quickly.

This isn't to say you should never consolidate your student loans. Sometimes it can make sense. But if you're comfortably keeping up with your student loan payments as they are, you're often better off leaving your loans alone.

5. Not shopping around for the best rates on private student loans

All federal student loan borrowers pay the same interest rate set by the government. This can fluctuate from year to year, but once you take out the loan, the rate is locked in. Private student loans, on the other hand, offer a variety of interest rates based on the creditworthiness of the borrower. Because many young college students don't have much of a credit history, this is often based on the creditworthiness of the cosigner.

As with any loan, it's always best to compare rates from multiple lenders to see which offer the best deals. A lower interest rate means you'll pay less overall, but you should also consider the repayment options, including opportunities for deferment and forbearance.

6. Choosing the wrong repayment plan

Private student loans may only have a single repayment plan, but federal student loans offer borrowers a variety of choices. Income-driven repayment plans are popular because they're tied to your income and you typically pay less per month than you would under the standard plan. But because you're paying smaller amounts each month, it takes longer to pay your loan off and you end up paying more in interest. 

Choose the repayment plan that offers the highest monthly payment you can comfortably afford if you want to pay as little as possible overall. Talk with your student loan servicer if you're unsure what your options are or how much the payments would be.

7. Ignoring loan forgiveness programs

The federal government offers several loan forgiveness and repayment programs to teachers, those in military service, and those who work in public service fields, like certain healthcare professions, to help these borrowers get rid of their student loans more quickly. These programs have strict requirements, so talk to your student loan servicer about what you must do in order to qualify, and follow the instructions to the letter. Errors like choosing the wrong repayment plan may leave you ineligible for loan forgiveness.

Some employers are now offering student loan repayment assistance as an employee benefit, so this is another option to consider if you don't qualify for one of the government assistance programs. Employer loan repayment programs may also enable you to use your funds for private student loans, unlike the government programs mentioned above.

You'll probably have to pay back quite a bit in student loans regardless, but you can save yourself a significant amount of money by avoiding the above mistakes.