While the IRS doesn't provide any resources for getting copies of W-2s online, it can provide copies of W-2s from previous tax years. Turnaround time for receiving these W-2s, which come attached to a copy of the tax return, is about 75 days, according to the IRS.
Because W-2s are generated by employers, the quickest way to get a copy of a W-2 form is often from that employer. Taxpayers can mail IRS Form 4506 to the IRS to get a copy of the return that includes the relevant W-2s; the form requires a fee. Form 4506-T provides a copy of the transcript of the tax return, which also includes the W-2 and only takes five to 10 days to process, as the IRS explains. Form 4506-T can also be faxed to the IRS.