How do I figure out if I will owe taxes
Your employer pays the expected (but estimated) taxes for you. So the chances are you don't own more; but that might be different if you have other sources of income that he doesn't know about (interest on savings or a side-job or whatever). Also, you could have deductions that reduce the taxes you owe, which he again doesn't know, so you overpay. If you don't file, you don't get them back. Most tax software companies offer free usage of their tool for standard filings, and you can use it to find out your tax situation, and then buy the tool only when you want to file. If you use one of those, you can type in all your data, and depending on the result, decide to buy it and file right away. Note that if it turns out you owe taxes, you must file (and pay), but of course you can do it manually instead of buying the tool. If it turns out you get money back, it is your decision to file - you probably don't care for a small amount, but if you get 1000 $ back, you might want to file - again, buying the software of doing it manually.