How is a Section 1045 rollover different from a 1031 exchange?
Both let you sell and reinvest without paying tax now. 1031 covers real estate, uses a 45-day identification period and 180 days to close, and requires a qualified intermediary. 1045 covers startup stock, gives you 60 days to buy, needs no intermediary, and can lead to a full exclusion rather than only a deferral.
Side by side
- Asset: 1031 is investment or business real property. 1045 is qualified small business stock held more than six months.
- Deadline: 1031 allows 45 days to identify and 180 to close. 1045 allows 60 days to buy, with no extension.
- Intermediary: 1031 requires one to hold the cash. 1045 doesn’t, so the cash comes to you and the clock is easy to forget.
- End state: 1031 defers. 1045 defers and can lead to excluding the gain under Section 1202.
Selling QSBS soon? Share your timing and we’ll line up qualifying rounds that close inside your window.
General information, not tax advice. Last reviewed November 2026.