If the amount you owe or the amount you overpaid is large, you may want to file a new Form W-4 with your employer to change the amount of income tax withheld from your 2010 pay. For details on how to complete Form W-4, see Pub. 919. If you have pension or annuity income, use Form W-4P. If you receive certain government payments (such as unemployment compensation or social security benefits), you can have tax withheld from those payments by giving the payer Form W-4V.
You can use the IRS Withholding Calculator at www.irs.gov/individuals
, instead of Pub. 919 or the worksheets included with Form W-4 or W-4P, to determine whether you need to have your withholding increased or decreased.
In general, you do not have to make estimated tax payments if you expect that your 2010 Form 1040 will show a tax refund or a tax balance due of less than $1,000. If your total estimated tax for 2010 is $1,000 or more, see Form 1040-ES. It has a worksheet you can use to see if you have to make estimated tax payments. For more details, see Pub. 505.