When paying off student loan debt, new grads should avoid these five mistakes

If you're graduating from school this year with a boatload of debt, you probably feel like things couldn't get worse. But don't worry: that couldn't be further from the truth.

There are a handful of mistakes new graduates often make when it comes time to pay back their loans. But if you tackle your student loan payments the right way, you will set yourself up for success and be debt-free in no time.

Here are the five biggest mistakes you should avoid as a new grad with student debt.

1. Missing payments

Rack up enough debt and you might feel like nothing you do will matter, so what difference does it make if you miss apayment here or there?

The reality is, it makes a big difference. When you miss a payment on federal loans, you're considered delinquent and will likely have late fees tacked onto your balance. And if your loan goes into collection, you could have the added expense of collection fees which can add anywhere from 18 to 40 percent to your total outstanding balance.

Missing payments for nine months would put you in default which may damage your credit and exclude you from government-sponsored student loan repayment and forgivenessprograms. If you have private student loans, missing payments is even more serious; you could be considered in default as soon as you miss one payment.

According to the Consumer Financial Protection Bureau, about 7 million student borrowers were in default as of last year. Don't let yourself become one of them.

2. Letting interest accrue during the grace period

If you have unsubsidized student loans, interest will start racking up as soon as they're disbursed. If you let that interest tack on during your grace period, the amount of money you owe on your loans can surge – even if you don't borrow another cent.

By making interest payments as soon as you can, on the other hand, you can save yourself from the horror of a ballooning loan thanks to interest charged on interest. Let's say you owe the average student loan debt for most graduates, which was a little over $35,000 in 2015. Your loans are unsubsidized and your interest rate is 6 percent. If you took full advantage of your six-month grace period, your balance would grow to more than $36,000 by the time you made your first payment. That's a high price to pay for just six months of freedom from repayment.

Don't delay making payments simply because you can. And definitely don't defer your student loan payments beyond the grace period if you can help it at all.

3. Believing you have no control over your monthly payments

When you borrow money for school, it's easy to assume you'll need to repay your loans using the 10-year Standard Repayment Plan. But if you're not earning a lot at the start of your career, those big monthly payments might be more than you can afford.

The mistake here is assuming you have no control. Under several income-driven repayment plans, the federal government has made it possible to make payments that actually jive with your monthly income. For example under the Pay As You Earn (PAYE) and Revised Pay As You Earn (REPAYE), borrowers can limit monthly payments to 10 percent of their discretionary income. Some borrowers even qualify for $0 monthly payments.

Income-driven repayment lets you cap payments at a certain percentage of your monthly discretionary income, usually culminating in loan forgiveness after 20 or 25 years. While you'll make payments on your loans a lot longer this way, you can still pay a lot less over the long haul if your income remains low enough.

4. Consolidating or refinancing without running the numbers

It can make sense to refinance or consolidate certain types of loans that charge high interest rates (e.g. Direct PLUS loans,which currently come with a rate of 6.84 percent), and there are times when refinancing or consolidating might even simplify your life.

Still, just because you can refinance or consolidate almost any type of student loan doesn't mean you always should. The reality is, refinancing doesn't always mean getting a better interest rate or a loan with better terms. In fact, there are plenty of scenarios where the new loan offered might be worse than the combination of loans you already have. For example, refinancing federal student loans with a private lender can cause you to miss out government protections, forgiveness, and repayment programs.

Always consider whether refinancing makes financial sense before you pull the trigger. If you're curious whether it makes sense, this refinancing calculator is a good place to start.

5. Failing to recognize the power of making small extra payments

By making small extra payments on a regular basis, you could take months or even years off of your repayment journey. Plus, you'll save money on interest, too.

Let's say, once again, you graduate with $35,000 in debt. Your loans come with an interest rate of 6 percent and you choose a 20-year repayment plan. In this scenario, your minimum payment would average out to $250, including principal and interest. If you could add just $45 to each monthly payment, you would cut five whole years off your repayment timeline and save $6,833 in interest in the process. And if you could find a way to boost that payment up to $390 each month, you would pay off your loans in 10 years and save $13,655!

Or, you could make those minimum payments for what seems like forever. The choice is yours.

Take student loan repayment seriously enough and you could dig your way out in a hurry, saving money and time in the process. On the other hand, the wrong repayment strategy could be costly — and add even more struggle to the burden of student loan debt. By avoiding the mistakes above, you can save yourself a whole lot of money (and headache) in the long run.

Commentary by Andrew Josuweit, CEO of Student Loan Hero, a a company that combines easy-to-use tools with financial education to help millions of Americans living with student loan debt. Follow him on Twitter @josablack.

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