Congress has rewritten the federal definition of "hemp," and the new definition starts to apply this fall. The change comes from Section 781 of the FY2026 agriculture appropriations act, which was signed into law on 12 November 2025 as part of Public Law 119-37. It counts THCA toward the THC limit, caps finished products at 0.4 milligrams of total THC per container, and removes cannabinoids that were "synthesized or manufactured outside the plant" from the definition of hemp.
The timing has already shifted once. Section 781 was written to take effect on 12 November 2026. A stopgap funding law signed on 2 September 2026 limits it, until 11 December 2026, to products containing cannabinoids the plant cannot naturally produce. Everything else, including the 0.4 mg cap, is scheduled to apply from 11 December 2026 unless Congress acts again.
I am a licensed California cannabis attorney and one of Proof's two founders. This article explains what the enacted text says, as of 23 September 2026. It is general information, not legal advice, and it does not predict how regulators or courts will apply the law.
Key takeaways
- The new federal definition of hemp counts total THC, including THCA, not just delta-9 THC.
- Final hemp-derived cannabinoid products (the finished products shoppers buy) may contain no more than 0.4 mg of total THC per container, combined with any cannabinoids that have similar effects to THC.
- Cannabinoids that are not naturally produced by the plant, or that are natural but "synthesized or manufactured outside the plant," fall outside the definition of hemp.
- As of 23 September 2026, the synthetic-cannabinoid piece applies from 12 November 2026, and the rest from 11 December 2026.
- Several key terms still depend on FDA lists and on how agencies read the text, so some questions are genuinely open.
Where the old definition came from
The 2018 Farm Bill defined hemp as cannabis "with a delta-9 tetrahydrocannabinol concentration of not more than 0.3 percent on a dry weight basis" (7 U.S.C. 1639o, Cornell LII). Because that test named only delta-9 THC, products built around other intoxicating cannabinoids, such as delta-8 THC made from hemp CBD, were sold nationwide as "hemp." Section 781 replaces that definition in full.
What Section 781 changes
The enacted text is in Public Law 119-37, Division B, Section 781 (GovInfo). Here is what it says, in plain language.
1. Total THC, including THCA. Hemp now means the plant and its derivatives "with a total tetrahydrocannabinols concentration (including tetrahydrocannabinolic acid) of not more than 0.3 percent on a dry weight basis." THCA is the acid form of THC that converts to THC when heated. The old wording named only delta-9 THC. The new wording expressly counts THCA.
2. A 0.4 mg per container cap on finished products. The definition excludes "any final hemp-derived cannabinoid products" containing "greater than 0.4 milligrams combined total per container" of total THC (including THCA) and "any other cannabinoids that have similar effects (or are marketed to have similar effects) on humans or animals as a tetrahydrocannabinol (as determined by the Secretary of Health and Human Services)." This cap is measured per container, not per serving and not as a percentage.
3. What counts as a "container." The law defines it as "the innermost wrapping, packaging, or vessel in direct contact with" the product as sold at retail, "such as a jar, bottle, bag, box, packet, can, carton, or cartridge." Bulk shipping containers and non-essential outer wrappings are excluded. For a tincture, that is the bottle.
4. Synthesized and converted cannabinoids are out. Both intermediate and final products are excluded from hemp if they contain cannabinoids "that are not capable of being naturally produced by a Cannabis sativa L. plant," or cannabinoids that "are capable of being naturally produced by a Cannabis sativa L. plant; and were synthesized or manufactured outside the plant."
5. Intermediate products have their own limit. Ingredients such as extracts and powders meant to be mixed into other products are excluded if they contain more than 0.3 percent combined total THC and similar-effect cannabinoids, or if they are "marketed or sold as a final product or directly to an end consumer."
6. The scope is broad. A "hemp-derived cannabinoid product" is any product derived from hemp that contains cannabinoids and is "intended for human or animal use through any means of application or administration, such as inhalation, ingestion, or topical application." That language reaches oils, topicals and pet products alike. FDA-approved drugs are excluded.
7. FDA was told to publish lists. Within 90 days of enactment (that is, by 10 February 2026), FDA was directed to publish a list of cannabinoids capable of being naturally produced by the plant, a list of THC-class cannabinoids naturally occurring in the plant, a list of other cannabinoids with similar effects to THC, and "additional information and specificity about the term 'container'." Those lists will shape how several of the provisions above work in practice. Check FDA's cannabis page for their current status.
When the changes apply
Section 781 opens with "Effective 365 days after the enactment of this Act." The act was approved on 12 November 2025, so that date is 12 November 2026.
On 2 September 2026, the Continuing Appropriations and Extensions Act, 2027 (Public Law 119-103) added a short extension. Its Section 2019 says that until 11 December 2026, the Section 781 amendments "shall only apply with respect to products described in paragraphs (1)(C)(ii)(I) and (1)(C)(iv)(I)" (bill text, Congress.gov). Those two paragraphs cover products with cannabinoids that the plant cannot naturally produce.
As of 23 September 2026, that works out to:
- From 12 November 2026: intermediate and final products containing cannabinoids that are not capable of being naturally produced by the plant are no longer hemp.
- From 11 December 2026: the rest of Section 781 is scheduled to apply, including the total THC standard, the 0.4 mg per container cap, and the exclusion of natural cannabinoids manufactured outside the plant.
The December date could move again. We will update this page if it does.
What it means for shoppers
Once the full definition applies, a finished product with more than 0.4 mg of total THC in the container is not hemp under federal law. Full-spectrum products usually contain small amounts of THC, and 0.3 percent of a product weighing about 30 grams is roughly 90 mg. So a full-spectrum oil can pass the old percentage test and still exceed the new cap, and some may not be sellable as hemp after the change.
What you can check yourself:
- Read the certificate of analysis (COA). Look for total THC in milligrams per unit (per container), not only a percentage.
- Check how total THC is calculated. Many labs report it as delta-9 THC plus 0.877 times THCA. See whether other THC forms, such as delta-8, were tested.
- Match the batch and date. The COA should match the batch on your bottle and come from an accredited third-party lab.
- Be wary of vague "THC-free" claims with no COA behind them.
Our guide to full-spectrum vs broad-spectrum explains why spectrum matters here, and how to choose a quality CBD product walks through reading a COA.
Where Proof stands, as of September 2026
Proof sells four hemp products online: CBD Comfort Drops, CBD + CBN Sleepy Drops, Ice Hot CBD Roll-On and Pets CBD Drops. The finished-product COAs from SC Labs for all four, dated May 2025, report total THC as not detected. You can read them on our lab testing page.
A "not detected" result is a good starting point, not the end of the analysis, because the new definition turns on more than the THC number. Sleepy Drops also contain CBN, and how the new exclusions and FDA's lists will treat CBN is one of the open questions under Section 781. We are working through it with counsel. We are not going to tell you any product is definitely unaffected before that work is done. We will update customers directly, and on this page, as soon as we have an answer.
What is still unsettled
As of 23 September 2026, these questions do not have final answers in the text alone:
- Which cannabinoids have "similar effects" to THC. The law leaves that to the Secretary of Health and Human Services.
- What "synthesized or manufactured outside the plant" covers, given that some cannabinoids on the market are made by converting another cannabinoid.
- How "total tetrahydrocannabinols" will be measured, including which THC forms count and how labs should report them.
- The FDA lists and the container definition, which the law directed FDA to publish.
- Further changes from Congress. The Congressional Research Service notes that other bills have been introduced to change the definition (CRS, Congress.gov). You can follow any bill's status on Congress.gov.
State law is separate. California, where Proof is made, already has its own rules for hemp products. The California Department of Public Health explains that since 2024 its regulations have required hemp foods, beverages and dietary supplements to have no detectable total THC, and that Assembly Bill 8 made further changes starting 1 January 2026 (CDPH AB 8 FAQ). If you live elsewhere, check your own state's agency.
FAQ
Is CBD illegal after November 2026?
Section 781 does not ban CBD by name. It narrows what counts as hemp. Products that exceed 0.4 mg of total THC per container, for example, fall outside the definition once that part applies (11 December 2026, as of 23 September 2026).
Does the 0.4 mg limit apply per serving or per bottle?
Per container. The law defines the container as the innermost package in direct contact with the product, such as the bottle.
Does the law cover topicals and pet products?
The definition of a hemp-derived cannabinoid product covers products intended "for human or animal use" through any route, and it names "topical application" as an example.
Will Proof's products still be available?
Our four products' May 2025 COAs show total THC not detected. CBN's treatment is still an open question, and we will update customers when we have an answer. For anything specific to your situation, talk to your own lawyer.
Related reading
- What's the deal with hemp and THC?
- The federal hemp ban explained
- Is CBD FDA approved?
- Why hemp product testing matters
- CBD vs CBG vs CBN
- The Proof Learn hub
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.