The IRS is not going to start accepting returns until January 13th so you might get your W2 by then or if your payroll department participates you might be able to download your information. Also, due to Congress late decisions some taxpayers will need to wait to file until mid to late February, see the following for more information
We urge you to WAIT!
You can use your last paycheck and enter it to get an estimate but be sure to come back and correct it when you get the W2.
WE'VE ALREADY HAD PEOPLE POSTING THEY FILED USING THEIR LAST PAYCHECK AND IT WAS NOT RIGHT!! NOW THEY HAVE TO FILE AN AMENDED RETURN!
See this postâ€¦
Filing a tax return before receiving your W-2 form(s) is not only discouraged, it is probably illegal as well. When you sign your paper return (or e-sign your e-filed return) you are certifying that your return is complete and accurate to the best of your knowledge, under penalty of perjury. If you paper file you must attach the W-2 to the tax return, if you e-file you must have the W-2 in your possession.
When you e-file you are certifying under penalty of perjury that the W-2 information came from your W-2 form and not from your paycheck stub.
[Paraphrased from IRS rules]
Can you file without having received your W-2? Yes, but ONLY if you have not received it by January 31, AND you have contacted your employer and attempted to obtain it, AND you still have not received it by February 14, AND THEN you contact the IRS (see the link below), THEN if the IRS is not successful in getting your W-2, you can use form 4852 in place of your W-2. But you MUST speak to the IRS before doing so.
Also see this:
In addition, the IRS will not be receiving e-filed returns until January 22 at the earliest (maybe later depending how long it takes to implement the new laws).