first you need your stock basis which you should be able to get from the 7203 you filed for 2022. then in 2023 there will be a proration of the income/loss between you and the new stock owner. your share of 2023 income/loss deductions and distributions will determine you basis on the date of sale. since it would seem you have held the stock long-term you would report the sale on schedule D. type F proceeds and tax basis not reported to the IRS. your capital gain/loss is the difference between the sales price and your tax basis. selling the stock and not the assets avoids the messier situation of depreciation recapture (ordinary income) and filing certain other forms.
this is with some caveats - depending on the date of sale the new owner may be able to revoke the S election effective with the start of the current tax year. sale to a related party at a loss would bar deduction of the loss.
However, if the S corporation was formerly a C corporation and is within the five-year built-in gains (BIG) tax recognition period, a sale of assets by the S corporation could trigger corporate-level BIG tax (Sec. 1374).
