Why is my second job affecting my tax return so much?

[mckaym11]

I filled out my entire tax information in turbotax (standard decuctions with student loan interest decucted) except for my second income (part time job) and had an estimated refund of $1492. When I entered my second W2, approximately $6800 extra in income, it lowered by refund by almost $1400. I am claiming single and 0 on the second job and the additional income didn't change my tax bracket. How is this affecting everything so significantly?

[mckaym11]

Thanks!

[Texas Roger · Accepted solution]

When you enter your first W-2, some part of it is not taxable because your standard deduction and exemption is subtracted from the income. When you enter your second W-2, all or most of your deductions are used up by the first W-2 so most or all of your second W-2 is totally taxable so it reduces your refund.

[mckaym11]

Thank you for the information! I added a few details into that question after I had accidentally posted it early. My second job, around $6800 in income was only 6 months worth of work. Going into this next year, do I need to with hold extra so that I don't owe at the end of the year when that extra income will be around double that?

[VolvoGirl]

That's common.  It just looks that way because you put them in as separate W2s and saw the tax due change in between them. If it all was on one W2 you would get the same answer. And each job was withholding like it was your only job.