It is too late to receive a tax refund for your 2015 tax return. If you owe tax due for the 2015 return, you still have to pay, though. TurboTax will not calculate the late filing penalty or interest--the IRS will bill you for that after they receive your return and your payment.
A 2015 return must be printed, signed and mailed, it cannot be e-filed.
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/state received the return.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**