Farms and supply
Lab testing for flower: when the sourcing rule needs a test per harvest
Thailand Cannabis Report · Reefers Club Co., Ltd. · Last checked 31 October 2026
Since 26 June 2025, a Thai cannabis shop has had to prove where its flower came from. For many growers, GACP certification is out of reach. The laboratory certificate of analysis, issued for each harvest, became the second way in.
The sourcing rule
The 2025 controlled-herb notification requires that flower sold by a licensee comes from a compliant source. Verified A notification gazetted on 12 September 2025 defined a certified source, with a per-harvest laboratory certificate of analysis as one route. On 1 May 2026 DTAM's grower guidance confirmed that either GACP assessment or a private-laboratory certificate qualifies a plot to supply a flower sales licence. Verified
How the timeline ran
- 11 July 2025: DTAM says every harvest must carry analysis results.
- 1 August 2025: DTAM makes acceptance of a laboratory certificate of analysis explicit.
- 12 September 2025: the certified-sources notification is gazetted.
- 1 May 2026: DTAM grower guidance confirms both routes.
What buyers should check
- The certificate matches the batch you are buying, harvest by harvest.
- It comes from a laboratory and names the farm or plot.
- The paperwork travels with the flower into your PT.27 records. See PT.27 and PT.28 explained.
- For GACP flower, the farm's certificate is current. See GACP certification.
The cost of uncertified stock
Under the guideline announced on 22 June 2026, selling or exporting flower not certified to GACP or an equivalent standard is a 30-day suspension. Estimated Under Ministerial Regulation No. 2, a suspension lets the authority consider refusing renewal.
Section 3 of the report, free to read, covers the sourcing rule. The report's supply section covers where dispensary flower actually comes from.
Sources
- Section 3 of the 2026 report, The rules in force (free to read)
- Thairath, DTAM guideline on administrative orders for cannabis shops, 22 June 2026
- Juslaws, Amendment to cannabis law on 25 June 2025
- Tilleke & Gibbins, Cannabis and Hemp Business Guide Thailand 2025
This article is market intelligence, not legal, tax or immigration advice. Rules change by notification; check the current text with the relevant authority or Thai counsel before you act.
In short
Do cannabis shops in Thailand need lab-tested flower?
Shops must sell flower from a certified source. A GACP-certified farm is one route; a laboratory certificate of analysis for each harvest is the other.
When did the lab test route start?
DTAM made acceptance of a laboratory certificate explicit on 1 August 2025, and a notification gazetted on 12 September 2025 set the per-harvest route.
Does the test have to be for every harvest?
Yes. The certificate route works harvest by harvest, not farm by farm.
What happens if a shop sells uncertified flower?
Selling or exporting flower not certified to GACP or an equivalent standard is a 30-day suspension under the June 2026 guideline.
Can private labs do the testing?
DTAM's May 2026 grower guidance accepts a private-laboratory certificate as one of the two routes.
Want the numbers behind this?
This article gives you the argument. The figures, where they come from and how sure we are of each one are in the report.