Why do i owe taxes

[coffeeme!]

I don't understand how I owe taxes when I did file last year taxes 

[ee-ea]

The best way to find out what happened is to make a line by line comparison of this return and the prior one(s).

[ThomasM125]

If you are a salary worker whose income is reported to you on a W-2 form, you may not have had enough taxes withheld from your pay. In this case, you should complete a new W-4 form for your employer and make sure you complete the form properly. Also, you can enter an amount on the W-4 form for additional taxes to be withheld from your pay. If you take your tax due and divide that amount by the number of pays your receive in a year, that is the additional amount you can have withheld from your pay to reduce the probability of owing taxes again next year.