Not every taxpayer is required to file a return. Depending on your income level, you may be entitled to claim more in deductions and credits than you’ve earned for the year. In these situations, you aren’t required to file a tax return since you have no taxable income to report to the IRS.

Let’s say you are a single taxpayer with less than $10,400 in income for the year. You won’t need to file a return because the standard deduction ($6,350) and the personal exemption ($4,050) you are allotted reduce your entire income amount to zero. The same is true for married taxpayers who earn up to $20,800 last tax year.

But did you know that just because you don’t have to file a tax return doesn’t mean you shouldn’t. You may be entitled to a refund just for filing, however you won’t know if you don’t file a tax return.

If you’ve received a tax credit to reduce the cost of your health insurance from the Marketplace, you’ll want to file a return to continue receiving the credits. You’ll receive a Form 1095-A, Health Insurance Marketplace Statement, to indicate that you received the credit. You’ll need to reconcile your credit by filing a tax return along with Form 8962, Premium Tax Credit, to calculate the difference between the credit you received and the credit you’re entitled to.

Should you fail to file, you’ll have to repay the amount of the credits you received, and you won’t be able to use any future tax credits toward your health insurance.

Also, some tax credits are refundable, so you should file a return if you’re eligible to claim any of these. The Earned Income Tax Credit (EITC) is an example of a refundable credit, available to low income workers. You’ll have to file a tax return in order to claim it, and it can be worth thousands of dollars, so it’s definitely worth it. You may still qualify even if you’ve paid no income taxes. The max amount of the EITC for 2017 is $510 per person with no children, and up to $6,318 with three or more dependents and certain income requirements.

The IRS reports that 27 million taxpayers who claimed the EITC were allotted a total $65 billion in credits. The average taxpayer received more than $2,400 by claiming the EITC, and some states offer a similar credit that can add more cash back.

However, the IRS also reports that one out of every five eligible taxpayers fail to claim the EITC. Taxpayers who earn less than $55,930 should definitely use the tools available on the IRS website to check their eligibility for the EITC.

You’ll need to file Form 1040, 1040A, or 1040-EZ with your correct earned income amount to claim the EITC. IF you have one or more qualifying children, you’ll need to attach Schedule EIC and provide the required information about those children to the IRS