The government emphasized that vehicle license plates marked "TC" and "QC" indicate authorized test vehicles used before production and for quality testing. These must comply with set conditions, with violations punishable by fines up to 2,000 baht.
On 6 Sep 2026 GMT+7, Ms. Ploythele Laksameesangchan, Deputy Spokesperson for the Prime Minister's Office, stated that following reports of vehicles displaying "TC" or "QC" license plates on the roads, the Department of Land Transport clarified that these plates signify authorized use for testing vehicle completeness and performance, assessing system readiness and standards prior to production. This ensures quality and maximum safety. The "TC" and "QC" plates differ as follows.
1. The "TC" license plate is for "pre-production test vehicles," which are prototype cars or motorcycles newly produced, assembled, imported, or modified in parts or equipment. Manufacturers must test these prototypes under real conditions to confirm quality and standards before full production. The authorization lasts 180 days from the approval date.
For cars: the plate is made of reflective white metal, measuring 15 cm wide and 34 cm long. The first line shows the letters "TC" followed by a number up to four digits. The second line displays "Bangkok" as the province, with the "ขส" mark embossed at the lower right corner.
For motorcycles: the plate measures 17.20 cm wide by 22 cm long and has three lines. The first line shows "TC," the second line displays "Bangkok," and the third line shows a number up to four digits. The "ขส" mark is embossed at the upper right corner.
2. The "QC" license plate is for "quality test vehicles," which are manufactured, assembled, or imported vehicles randomly sampled for quality testing before sale. The plate measures 15 cm wide by 34 cm long. The first line shows "QC" followed by a number up to four digits. The second line displays "Bangkok" as the province, with the "ขส" mark embossed at the lower right corner. The authorization is valid for 90 days from the approval date.
“Vehicles bearing "TC" or "QC" plates must carry a copy of the authorization letter with the vehicle throughout the testing period and have insurance evidence as required. Test drivers must hold a valid license appropriate for the vehicle type. Any authorized user violating or failing to comply with these conditions commits an offense under Section 6/1, paragraph three, and is subject to penalties under Section 60 of the Motor Vehicle Act, 1979, with fines up to 2,000 baht,” Ms. Ploythele said.