If the 1099-S was for the sale of your main home, it’s reported under Less Common Income in the Wages & Income section.
https://ttlc.intuit.com/replies/3302480
To enter information from Form 1099-S Proceeds from Real Estate Transactions in TurboTax:
- Go to Federal Taxes
- Select Wages & Income
- Click I'll choose what I work on
- Find the Investment income section
- Select Start next to Stocks, Mutual Funds, Bonds, Other
- On the Let Us Enter Your Investment Sale Info screen, select I'll Type it in Myself
- Select No financial Institution on the next screen
- Follow the on screen prompts
This article has additional information regarding Form 1099-S:
http://www.irs.gov/pub/irs-pdf/i1099s.pdf