United States Revises Hemp Definition, Tightening THC Limits

The 2018 Farm Bill defined hemp as Cannabis sativa with a THC concentration of no more than 0.3% by dry weight. A new rule set to take effect in November changes the definition to a plant‑level THC limit of ≤0.3% and a per‑container total THC limit of 0.4 mg, substantially reducing the number of products that qualify as hemp. The update is linked to a broader rescheduling effort that would move hemp into Schedule III, reuniting it with marijuana under a single schedule, while synthetic cannabinoids would remain in Schedule I. As the Federal order noted, “some full‑spectrum CBD products will once again be controlled as marijuana.”

Hemp and marijuana differ primarily in THC content. Hemp is cultivated for low THC and high CBD, fiber, seeds and oil, and is federally legal under the revised threshold. Marijuana is bred for high THC, used recreationally and medically, and remains a Schedule I substance. The regulatory shift affects manufacturers, retailers, and consumers of CBD and other cannabis‑derived products across the United States.