Hemp
Definition: Hemp is the federal legal category for Cannabis sativa L. at or below 0.3% THC on a dry-weight basis. Since the 2018 Farm Bill that limit has been measured by delta-9 THC alone, but Section 781 of H.R. 5371, signed November 2025, moves to a total-THC standard, with most changes effective December 11, 2026.
How Hemp works
Hemp and marijuana are the same plant species. The line between them is a legal threshold, not a botanical one, and that threshold is changing.
The 2018 Farm Bill standard
The Agriculture Improvement Act of 2018 defined hemp as Cannabis sativa L. and any part of it, including its seeds, derivatives, and extracts, with a delta-9 THC concentration of not more than 0.3% on a dry-weight basis. Cannabis above that line is marijuana, a federally controlled substance. Because seeds carry only trace THC, seed sellers have generally treated cannabis seeds as hemp under this wording.
What Section 781 changes
Section 781 of H.R. 5371 (Public Law 119-37), signed November 12, 2025, rewrites the definition:
- The 0.3% limit applies to total THC, which counts THCA along with delta-9 THC.
- Viable seeds from a cannabis plant above 0.3% total THC are excluded from the hemp definition, removing the basis for treating seeds of marijuana strains as hemp.
- Final hemp-derived consumer products are capped at 0.4 mg of combined total THC per container, and cannabinoids not naturally produced by the plant are excluded.
Effective dates
The changes were scheduled for November 12, 2026. H.R. 6500 (Public Law 119-103), enacted September 2, 2026, moved most of them, including the total-THC standard and the seed exclusion, to December 11, 2026. The exclusion for cannabinoids not naturally produced by the plant kept the November 12 date. Congress could revise these timelines again; the Congressional Research Service summary tracks the details.
State law separately decides whether you may grow. See our guide to seed legality in the US. This is general information, not legal advice.