Click "Continue" /edit on the first screen to confirm your business information.
Check the box labeled "The business is closed."
Enter the Closing Date:
When you get to the question marked "The business closed," click "Date you closed the business" and enter the closing date.
Verify the Final Return Box:
TurboTax will automatically check the applicable box on Form 1120-S.
To ensure the box is checked, go to Tax Tools, then Tools, click on Tax Summary, and then click on Preview my 1120-S to double-check that the final return box is checked on Page 1.
Option 2 - To mark this as your final 1120-S enter your K-1 for your S-Corp (Form 1120S) in TurboTax, follow these steps: