No, you can't combine tax years; you must report all of your income. If you have already e-filed or mailed the return and they accept it, then you will need to wait until you have received
your refund. Then, you will need to amend that return to make changes (add your
additional W-2). You will need to send in any forms that caused the need for an
amendment (Original 1040 Form, new 1040X Form and additional W-2). Print, sign
and mail your forms to the IRS.
Click here for instructions for amending a return.
