@marcisikoff --
"Why is K-1 income to a partner not allowed to flow to their Sole Proprietor Schedule C as income?"
Schedule C is for reporting of sole proprietorship income & expenses. K-1 partnership income from an LLC is not sole proprietorship income.
Do you & your wife own the LLC? If a husband & wife form a qualified joint venture ("QJV") they would each be able to report their share of the business income on Schedule C. According to this web reference from LegalZoom, if your LLC was formed in a community property state, you may be able to file as a QJV:
https://www.legalzoom.com/articles/managing-and-forming-a-qualified-joint-venture
You may want to seek professional assistance.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
