I am e-filing and sending a check. What paperwork do I need to send in?

You should have a voucher to print. It's a 1040-V. You will mail that with your check.

Just the 1040-V? Do I need to include a W2? 

do not submit the w-2 SINCE YOU AR E-FILING YOUR RETURN.  when you mail the check make you  follow Turbotax instructions for the additional info you have to write on the face of your check

1) payable to US Treasury

2) your SSN'

3) 2024 FORM 1040 

Thanks!

😄