In order for SCorp K-1 income to be included in QBI calculation, there must be amounts in Box 17 with codes in the V to Z range. See the Box 17 code explanations attached below. In addition, you must get all the way through the K-1 entry for the QBI deduction to calculate.
The QBI is a personal income tax deduction and will be reported on line 9 of the 1040 form.
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