A couple of follow-up comments:
- Based on what you are saying, it doesn't sound like you have any carryover to 2017. TT would not have limited the loss unless you had indicated that you were passive or were limited in basis.
- Having said that, it is extremely important that you track your basis in the S corp stock. This begins with your initial capital contribution and is adjusted annually for the applicable lines on your K-1. See the attached link from the 2018 S corp K-1 instructions page 4 on updating your basis:
https://www.irs.gov/pub/irs-pdf/i1120ssk.pdf
Unless you properly maintain your basis, you will not know if you are able to take losses, if distributions are tax-free or taxable, or determine your gain or loss upon the sale or liquidation of your stock.
*A reminder that posts in a forum such as this do not constitute tax advice.
Also keep in mind the date of replies, as tax law changes.
