The amount of income taxes withheld from each paycheck is based on the assumption that you will make that amount of money for every pay period of the year. Thus, if you have 8 months at regular pay (with no overtime), you will have had withheld approximately 8 months of what your yearly taxes would be if you work the same schedule for 12 months, but for the remaining 4 months of the year, the amount of taxes withheld will be based on your making that higher amount for the entire year.
In your specific case, it appears that, without the overtime, you were very close to the dividing line between tax rates. Of course, not knowing all the details (and not being knowledgable enoungh to work with those details should I have them), I can't give you an exact answer. Below, from
Yahoo.com's Tax Center, are figures for taxes that were due on April 15, 2005.
Married filing jointly or qualifying widow/widower Income Range - $14,301 - $58,100
Tax Rate - 15%
Married filing jointly or qualifying widow/widower$58,101 - $117,250
Tax rate - 25%
You will probably be in the 25% bracket for this year. Whether or not you were in this bracket last year depends on many things, but you should be able to figure this out. As I said above, your particular situation puts your previous income very close to the dividing line between brackets. Once you have figured this out, you can easily figure how much you have already paid and what your probable income and tax obligation will be for this year.
