I have my 1st RSU sale and I am planning on e-filing. What additional documentation is required to be sent to the IRS and where do I send it?

[MayaD]

You don't need to send any additional documentation to the IRS.

When your shares vest your employer calculates an amount of compensation for those shares, and reports that in Box 1 of the W-2, so you're going to pay taxes on that compensation.

You need to enter form 1099-B to report the sale of the shares and put in the cost basis so you are not taxed on the sale of the shares twice.