W-2s are filed with the Social Security Administration (SSA) in winter. Corrections, which are made on Form W-2c, begin immediately thereafter. The earlier you fix errors on your W-2s, the less likely it is you’ll be penalized by the IRS. E-filers have until the end of March to file their original W-2s But even those few extra weeks will not be enough to get off the W-2c hook, if errors are discovered after filing.
Forms W-2c/W-3c. Corrections to W-2s are reported on Form W-2c; Form W-3c is the transmittal. W-2c forms may be filed on paper or electronically. E-filing is mandatory if you’re filing 250 or more W-2c forms. Forms should be filed as soon as errors are detected, but to avoid multiple filings you may bundle corrections and file by Aug. 1, 2014.
COUNT CAREFULLY: If you file 200 W-2c forms in March and another 30 forms in May, you don’t have to e-file. Flip side: If you file an additional 100 W-2c forms in May, e-filin...(register to read more)