Thats the thing about Thailand and the enforcing of the different laws - its often totally random and far beyond understandable for a person of western origin.

Before Covid this law were partly enforced, some bordercrossings always enforced, some bordercrossings sometimes enforced and sometimes not. Other bordercrossings never enforced, well until they started enforcing them.

Post-Covid it seems that all overland travellers have been able to enter Thailand without guides and permits. But you never know, maybe one day they start to enforce this law again…?

Time for your vehicle in Thailand. Usually you got 30 days TIP and those 30 days could be extended up to 180 days, extensions 30 days at a time. However this was always up to the discretion of the local custom officer. In Chiang Mai they did it - albeit a little bored of it, in Udon Thani no way, in Ranong they were very happy to give me an extension and actually gave me a few days extra to align with my visa and they also gave me coffee and biscuits while the paperwork was done. So all I can say is that it usually works out. Be polite and respectful and boast a little of how much you like the country and its people, food and scenery and it will boost your chance to get an TIP exstension….

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In the end everything will be fine. If its not fine its not the end....