I am wondering if I need to review my W-2 and make sure that my exemptions are correct.
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How many exemptions should I be claiming?
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I don't remember my return being significant last year, but I don't think I had to pay in.
Feege, welcome to the forums.
Reading between the lines of your posts, it appears some financial self-study would benefit you. Fortunately, given your already-busy life, it shouldn't take much time and the benefits should make it worthwhile. Some steps you could take:
1. Get a previous tax return that you trust is correct.
2. Get some tax preparation software. See
http://taxes.about.com/od/taxsoftware/tp/taxsoftware.htm for several suggestions. If you have Excel 2010 or later,
https://sites.google.com/site/excel1040/ is one good choice; TaxAct, TurboTax, etc. are also good programs.
3. Use the tax prep software to reproduce the return you have from step #1. Note: if you used a program to do those taxes, then you have already done steps 1, 2, and 3.
4. Take your best guess at 2014 numbers, put them into the tax prep software, and predict your 2014 taxes. If the software is for 2013 instead of 2014, that should be ok for your purpose here.
5. Compare your estimated tax due with the amount already withheld, calculate the difference to determine the amount you need to withhold for the rest of 2014, and adjust your W-4 exemptions to get that amount withheld. See
http://www.halfpricesoft.com/federal_income_tax_2014.asp (Table 4) for one list of the withholding tables. E.g., if you are paid monthly, one exemption is worth $3950/12 = $329.2. Subtract any pre-tax deductions and $329.2 * NumberOfExemptionsYour from $2900 to get taxable income, and your employer should withhold $75.60 plus 15% of the taxable income over $944.00.
Or you could go to
http://www.irs.gov/Individuals/IRS-Withholding-Calculator and use that, which takes you through all the steps above.
Good luck!