Employers/contractors must furnish forms W-2 and 1099 to the employee/recipient on or before January 31 for the prior year. If employment terminates before the end of the calendar year the W-2 form must be furnished within 30 days. IRC § 6051(a).
If the taxpayer (employer) is filing more than 250 Forms 1099 series and W-2, or other “information return” form required by the applicable regulations or revenue procedures, the filing must be submitted on magnetic media. Returns made on a paper form must be machine-readable if applicable revenue procedures provide for a machine-readable paper form. Reg. § 301.6011-2.