Im trying to understand the complicated Thai laws to do with visas..

So to put your 90 day visa back to day one, all you have to do is walk across the border and walk back?

Do you have to stay over night?

Does it cost anything?

this law is hilarious?

A 90 day entry is just that - 90 days. A border crossing and return would only get a visa exempt entry (for most people 15 days). If you are talking about a multi entry non immigrant visa then a border crossing/return gets a new 90 day stay on any entry. No you do not have to stay overnight but some borders will try to get an extra payment from you if you do not. It costs whatever the other country charges for entry if you do not already have a visa.

Dont forget you have to stamp out of Thailand Stamp into a neighboring country (with appropriate Visa) stamp out of that country before re-entering Thailand.

Dont think like some have in the past, you can just stamp out walk the other side of the road and stamp back in, that wont work.

Dont forget you have to stamp out of Thailand Stamp into a neighboring country (with appropriate Visa) stamp out of that country before re-entering Thailand.

Dont think like some have in the past, you can just stamp out walk the other side of the road and stamp back in, that wont work.

And all this can be done at the border, correct?

Dont forget you have to stamp out of Thailand Stamp into a neighboring country (with appropriate Visa) stamp out of that country before re-entering Thailand.

Dont think like some have in the past, you can just stamp out walk the other side of the road and stamp back in, that wont work.

And all this can be done at the border, correct?

If using Nong Khai as an example, then yes, you exit Thailand, get bus over the bridge, get a visa as you enter Laos and you're stamped in, walk around the building, stamp out, back on the bus to Thai side, stamp back in to Thailand, dependant on time of day how busy etc its about 45 minutes over and back.

Edited April 22, 201214 yr by CharlieH

Depends on your visa, if it is multiple entry non-immigrant visa then, yes.

In the title you mention 90 day tourist-visa, there are no 90 day tourist visa.

Tourist visas gives you 60 days on entry, that can be extended with 30 days at immigrations.

90 day entries are given on non-immigrant visas.

Edited April 22, 201214 yr by PoorSucker

I am courious what does the Op consider complicated about Thai visa laws and rules, it appears his knowledge is lacking about these laws and rules. If you supplied the thread with proper information then you question could be answered.