The Department of Land Transport clarified the case of unusual vehicle license plates with the letters TC and QC seen on roads, confirming they are legal markers used for performance testing before actual production and quality testing before sale.
Mr. Thitiphat Thaichongrak, Director of the Automotive Engineering Bureau and spokesperson for the Department of Land Transport, stated that regarding images showing vehicles with license plates bearing the English letters TC or QC on the roads, the Department of Land Transport
would like to explain that license plates with the letters TC and QC are authorized markers issued by the Department permitting vehicles to be used for testing the completeness and performance of the vehicle, assessing the readiness of various systems, and ensuring standards before production, which helps guarantee quality and maximum safety.
The Department of Land Transport categorizes test vehicle license plates into two main types based on their purpose, as follows:
"TC" (Test Car) license plate
Purpose: Used for "pre-production test vehicles," which are prototype cars or motorcycles newly produced, assembled, imported, or modified with components and equipment to test performance and efficiency under real usage conditions before market release.
Validity: The authorization is valid for 180 days from the date of issuance.
Plate characteristics
For cars, the plate is a white reflective metal plate measuring 15 cm wide by 34 cm long. The first line shows the letters "TC" followed by up to 4 digits. The second line reads "Bangkok" and there is an embossed "กส" mark at the lower right corner.
For motorcycles, the plate measures 17.20 cm wide by 22 cm long, with three lines: the first line shows "TC," the second line "Bangkok," and the third line up to 4 digits, with an embossed "กส" mark at the upper right corner.
"QC" (Quality Control) license plate
Purpose: Used for "quality test vehicles," which are vehicles that have been fully produced, assembled, or imported and are randomly selected for final quality testing before being released for public sale.
Validity: The authorization is valid for 90 days from the date of issuance.
Plate characteristics: A white reflective metal plate measuring 15 cm wide by 34 cm long. The first line shows the letters "QC" followed by up to 4 digits. The second line reads "Bangkok" and an embossed "กส" mark appears at the lower right corner.
Rules and penalties for violations
The Department's spokesperson added that vehicles bearing TC or QC plates operating on highways or public roads must strictly comply with legal conditions, including:
Carrying a copy of the authorization letter at all times during testing.
Possessing insurance evidence as required by law.
The test driver must have a valid driving license appropriate for the type and characteristics of the vehicle.
If the authorized person uses the vehicle in violation or fails to comply with conditions, it constitutes an offense under Section 6/1 paragraph three and is subject to penalties under Section 60 of the Motor Vehicle Act B.E. 2522, with fines up to 2,000 baht.
If the public or operators have further questions, they can contact the Vehicle and Engine Account Control Division, Registration and Tax Standards Bureau, Department of Land Transport at 0-2271-8888 ext. 2408.