Why do I owe when I just started working at Walmart it's been only 4 months

You posted your question from a version of online Live software.  If you are really using that “Live” software you can get help from your “expert.”

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It depends.  If you are being claimed as a dependent on another person's tax return (usually a parent), then it's possible you could owe tax.  If not, then you may have made an amount over the filing requirement which would create a tax liability.  There are more tips in the link below which may be useful when you review your return.

• Why do I owe tax?

You may want to review your Form W-4 to see if you completed it they way you wanted to.  Walmart or any company uses this to calculate how much to withhold from each pay check.

• TurboTax W-4 Calculator
• Form W-4 and Your Take Home Pay

You have the ability to preview your tax return before you file.

Using the Tax Tools:

• To find Tools: 
  • Sign into your TurboTax account and open or continue your return. 
  • Select Tax Tools in the left menu. 
  • You'll find Tools beneath Tax Tools.
  • Select View Tax Summary
  • Select Preview My 1040 (left)