THCA (also THCa, THC-A, or THC A) is one of the latest alternative cannabinoids shaking up the hemp market. THCA, short for tetrahydrocannabinolic acid, is unique because it occurs naturally in the plant and transforms into psychoactive THC when heated and smoked. High THCA hemp products get people high and are broadly available nationwide. 

This guide explains THCA legality in the U.S., including the current THCA legal status in each state and where consumers can find legal THCA for sale. 

Most people are familiar with Delta-9 THC (or THC for short), the primary cannabinoid in cannabis and hemp responsible for the plant’s intoxicating effects, such as euphoria, relaxation, and pain relief. Federal law lists Delta-9 THC as a Schedule I controlled substance.

THCA is the acidic form of THC. THCA isn’t psychoactive in its raw state because it has a slightly different molecular shape that prevents it from binding to receptors in the brain and central nervous system as Delta-9 THC does. 

However, applying heat to THCA’s will chemically transform its shape into Delta-9 THC in a process called “decarboxylation.” Smoking, vaping, dabbing, or cooking cannabis for edibles are all sufficient ways to heat and “decarb” the THCA into THC, making it highly psychoactive. Learn more about the difference between THC and THCA in our guide.

The DEA lists Delta-9 as a banned substance. However, it does not include THCA on its Controlled Substances list, likely because THCA is not psychoactive in its natural form. As a result, THCA products are federally permitted, or at least exist in a gray area. 

Additionally, the USDA’s Farm Bill makes THCA legal when derived from hemp that contains less than 0.3% Delta-9 THC by dry weight. Farmers must test pre-harvest hemp samples with verified third-party laboratories to determine compliance, factoring in total THC content post-decarboxylation (heating). 

Industrial hemp that passes the USDA’s testing requirements and hemp products that contain less than 0.3% Delta-9 THC is federally legal. As a result, hemp companies and brands can produce products with high THCA levels, such as Qwin’s new line of THCA flower and vapes.