first contact employer to correct or explain why the number is correct.
if employer refuses
Contact the IRS and file a complaint if your W-2 is obviously and significantly wrong and you suspect dishonesty on the part of your employer. The IRS will investigate the matter directly with him. You can call the IRS toll-free at 1-800-829-1040.
You can also report an incorrect W-2 by following instructions made available on the IRS website. Then you can file your tax return reporting what you think is the correct amount of wages and withholding using Form 4852, Substitute for Form W-2. You will have to reference your pay stubs if you use this form. The IRS might take longer to process your tax return because it must verify the amounts on Form 4852 and it may contact you with any questions
