I want to file my tax returns early can I file my taxes with my last pay stub?

Yes, as long as the year-end data is accurate and properly reflects what taxes were withheld.

If you use tax software, you can enter the data in the W-2 screen, then print that W-2 off to attach to your tax return.

The IRS will also accept a photocopy of your check stub in lieu of the W-2.