The short answer: hemp derived THCA under 0.3% Δ9 THC is federal hemp under the 2018 Farm Bill, and a number of states restrict it anyway. The long answer is below, stated as plainly as the subject allows. This file is information, not legal advice.
The federal rule
The Agriculture Improvement Act of 2018 removed hemp from the Controlled Substances Act and defined it by one measurement: cannabis with no more than 0.3% Δ9 tetrahydrocannabinol on a dry weight basis is hemp, and its cannabinoids and derivatives are hemp products. The statute names Δ9 THC as the yardstick. THCA is a different compound, so flower rich in THCA that stays under the Δ9 threshold fits the federal definition of hemp. That chemical distinction, one heat step wide, is explained in the comparison file.
The honest complications
Anyone selling certainty here is overselling. Three things complicate the clean federal picture. First, USDA rules require growers to pass a total THC test before harvest, which counts THCA at its converted value; that governs farming, while products after harvest are generally assessed on the Δ9 definition. Second, the DEA has issued interpretive statements about post harvest testing that lawyers continue to argue over. Third, and most practically: states write their own laws, and the state rule is the one that shows up at your door.
Where states land
States sort into three rough camps. Some follow the federal Δ9 definition and allow compliant THCA products. Some apply a total THC standard that counts THCA toward the 0.3% limit, which closes the category. Some restrict smokable hemp entirely regardless of chemistry. These laws move, sometimes mid year, so the house maintains a current do not ship list instead of quoting a table here that would age badly.
The house position: we do not ship to states where THCA products are prohibited. No exceptions, no winking workarounds. If checkout accepts your address, our current legal review permits shipping there. Knowing your local law remains your responsibility.
What a compliant operation looks like
Compliance is visible if you know where to look. Every product carries an accredited laboratory certificate proving its Δ9 THC sits under 0.3% on a dry weight basis, published in the certification library and matched to the exact batch. Age is verified at 21 or older on every order. Marketing stays truthful: no medical claims, no legal promises a statute does not back. That is the standard this house runs on, and it is the standard you should demand from anyone in this market.
Two final cautions
First, THCA converts to THC with heat, and its metabolites fail drug tests. If you are subject to screening, this category is not for you, full stop. Second, laws change faster than articles. This file is reviewed and updated, but when a purchase decision turns on a point of law, verify your state's current rule or ask a professional. The house will keep its side of the record current.