I have both Federal and State taxes printed out and was wondering if I could mail both of them at the same time or should I mail Federal taxes first?

Yes you can certainly mail them both at the same time. You would need to mail your Federal tax return to the IRS and your state return to your state tax agency. Please be sure to follow the instructions that printed out with your tax returns, this will tell you where you should mail your Federal return and state return.

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s.  Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return.