Due to the language barrier that arises from the use of Thai and Romanised scripts for vehicle plates registered in Thailand and Malaysia, respectively, road vehicles crossing the Malaysia–Thailand border are typically required to bear stickers in the front and back that translate the characters of the plates into those understandable in the country of entry.
Although this is not a mandatory requirement under the ASEAN Accord for vehicles having Romanised plates, some Malaysian vehicles traveling beyond 50 kilometres of the Malaysia–Thailand border may bear permanent stickers that translate Romanised letters of the Malaysian number plates into Thai, but are otherwise identical in both the use of numerical characters and colour schemes; however, a note to indicate *(STATE)*MALAYSIA* under the vehicle registration is obligatory. The stickers do not have to be removed upon re-entry into Malaysia. Entering heavy goods vehicles from Malaysia are also required to bear a separate Thai Trade Registration Number with yellow plates denoted by the 70-xxxx or 7x-xxxx series.
Entering Thai-registered vehicles, which use the Thai script for series letters and the province of registration on their number plates, are required to bear strips on the front and back that translate the plate information into a row of Romanised script (including the corresponding series prefix and 4-digit number, and the province in its official 3-letter abbreviation), resulting in a format that reads as AB 1234 PTN or 1AB 1234 BKK.[25] Although the general practice is to use white characters on black, stickers with colour schemes that resemble their original plate colours may also be acceptable; stickers that emulate the layout and colour of the Thai plates have also been known to be used.