Each year, millions of Americans eagerly await their tax refunds once their returns are submitted. For some, having that money means paying off debt or covering a bill that's soon to come due. For others, it means having more breathing room in their monthly budget. But before you make plans to use that refund, you should know that in some cases, that money may not actually hit your account. Here are a few scenarios where your tax refund can be withheld.

1. You owe back taxes

If you owe money on your taxes from a previous year, the IRS can garnish your refund and use that money to offset your outstanding balance. In other words, if the IRS owes you money this year, but you owe it more from a previous year, the agency will choose to pay itself first, which does make sense. Incidentally, you risk having your refund garnished if you owe state taxes as well.

Post-it note with the words tax refund tacked onto a paper tax return

IMAGE SOURCE: GETTY IMAGES.

2. You're behind on child support payments

The government doesn't take kindly to people who don't make good on their financial obligations to their children. If you have outstanding child support payments you've yet to make, the government can seize your tax refund and give that money over to your former spouse, or whoever's entitled to that child support.

3. You've defaulted on a federal student loan

You need to go a full 270 days without making a payment to reach the point of having defaulted on a federal student loan. But once you hit that threshold, the government has the right to take your refund and apply it to the balance you owe.

Protecting your tax refund

The best way to ensure that you get to collect your tax refund? Don't be delinquent with the payments you owe. If you have outstanding tax debt, reach out to the IRS and see about getting on an installment plan to pay it off. If you owe money in child support, make good on that agreement. And if you're withholding child support not out of malice, but due to a lack of funds, reach out to the person eligible for that support, along with a lawyer, and try to come to some sort of arrangement.

Meanwhile, if you owe money in federal student loans but can't make your payments, you have several avenues to pursue before reaching the point of default. First, you can apply for an income-driven repayment plan, where your monthly loan payment will be calculated based on your earnings, not just based on your loan amount and interest rate. Another option is to apply for deferment or forbearance, both of which allow you to stop making loan payments for a period of time without it being held against you.

Though your tax refund isn't free money -- it's money you earned the previous year but never collected -- in some situations, you may not be entitled to it. Knowing when your refund can be garnished could help you avoid a scenario where that actually happens.