New 120km/h speed limit will not apply in Phuket New 120km/h speed limit will not apply in Phuket PHUKET: The move to increase the speed limit on roads throughout the country designated as highways to 120km/h will not apply anywhere in Phuket, as none of the major roads on the island satisfy the criteria for the speed limit increase, the Phuket Highways Office has confirmed. The 120km.h speed limit will not apply to any roads in Phuket. Photo: The Phuket News The news follows the Cabinet earlier this month approving the move ‘in principle’ to increase the speed limit on highways ro 120km/h, but left the actual implementation of the law change to the Transport Ministry. The speed limit change has yet to come into effect.