Read this now, once, while nothing has happened. It takes three minutes and it is the difference between handling a crash in Thailand and being handled by it.
Then print it, or save the page, and put it somewhere you will find it with one hand.
The single most important thing: in Thailand you generally wait at the scene for the police and for the insurance company's surveyor. Exchanging details and driving off, which is normal in most of Europe and North America, will usually cost you the claim. See why you wait.
At the scene
1. First sixty seconds
2. Make the calls
3. Stay put and record it
4. What not to do
5. Before you leave the scene
6. Afterwards, even if you feel fine

Numbers, in one place
| Number | Who answers | When to use it |
|---|---|---|
| 1669 | Emergency medical services | Anyone is injured. This is the first call. |
| 1155 | Tourist police | You need English, or help dealing with the situation. |
| 1193 | Highway police | On a highway. |
| 1543 | Expressway Authority | On an expressway. |
| 1586 | Department of Highways | Road condition, an obstruction, damage to the road. |
Keep the full emergency numbers card on your phone as well — it has the Thai phrases to read down the line if nobody at the other end speaks English.
The parts most people get wrong
Waiting. It feels absurd to sit at the roadside for an hour after a minor bump. In Thailand it is what the system expects, and the insurer's surveyor attending the scene is the mechanism by which fault and payment are settled. Leave early and you have usually forfeited the argument. Full explanation in should you call the police and the surveyor at the scene.
Fault. It is not decided the way it is at home, and being foreign is neither automatically against you nor automatically in your favour. See how fault is decided.
Cover. If you were riding without the entitlement your policy requires, the claim can fail regardless of who caused the crash. That is worth knowing before you ride rather than after — see what voids your cover.
The full guide, with everything this card compresses, is what to do after a road accident. If the vehicle is a hire one, read accidents in a rental too — the commercial side runs on a separate track from the legal one.