Do I need to send the paper copy of W2C to IRS if I have not filed 2018 tax return yet? I have filed for an extension waiting for this W2C which I finally received.

Instruction that came with the W2C states:

"If you have not filed your return for the year shown in box c, attach Copy B of the original Form W-2 you received from your employer and Copy B of this Form W-2c to your return when you file it."

I'm e-filing thru TurboTax.  Do I need to send in a paper copy of the W2 and W2C?

Thanks!