A w-2 form tells your employer what percentage of your income you want withheld for income taxes. You can send them a "corrected" or change form anytime, but it will usually not take effect for one or two pay periods. Sometimes, when a bonus is expected, people will change their withholding to get a higher amount, and then change back.
The employer is required to provide it to you as a paper document by January 30. You'll need to talk to your HR department if you want an online copy.
When they send you the 1099 for your winnings last year it will be listed on that form.
You can change your address on your W-2 before it comes by notifying the Internal Revenue Service (IRS) of your new address.
You'll need to fill out Form 8822 (Change of Address form). The form is located online here: irs.gov/pub/irs-pdf/f8822.pdf. The IRS states that you can fill out the form and submit it at any time during the year, although you may want to consider submitting it before the end of the calendar year. According to TurboTax, employers are required to send you your W-2 no later than January 31, so it would be advisable to submit the form before then.
You can also give the IRS written notification of your new address by sending a letter to the IRS center where you file your return, or by speaking to an IRS employee in person or over the phone. You'll need to include your name, date of birth, Social Security number, and old and new address.
If you are not concerned about changing your address on your W-2 before it arrives, you can always write your new address in the appropriate boxes on your tax return when you file.
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