Is any one aware if on a land crossing border run, 30 days stay is given for certain nationalities rather than the usual 15 days?

Will not mention the nationalities at this time but yesterday I witnessed border crossing stamps for 2 people who had just returned from a border run. One was for 15 days and the other was 30 days. The guy with the 30 day stamp said friends of the same nationality had often got 30 days. Strange!

Not strange, just some countries have different agreements with Thai Immigration.

Malaysian nationals get 30 days when entering Thailand on a land border from Malaysia.

Source: http://www.immigration.go.th/nov2004/doc/temporarystay/policy778-2551_en.pdf

so do laos

So do Russians.

Some Nationals get 90 days.

So do Russians.

Some Nationals get 90 days.

Where can I find the authority (and countries list)? The 2 instances I initially referred to were Danish 15 days / Russian 30 days.

http://www.mfa.go.th/web/2482.php?id=2495

http://www.mfa.go.th/internet/document/ChartVisa.pdf

II. List of countries which have concluded agreements on the exemption of visa requirements for holders of ordinary passports with Thailand and permitted to stay for a period of not exceeding 14, 30 and 90 days

14 DAYS

1. Combodia

30 DAYS

1. Hong Kong SAR (***)

2. Laos

3. Macau SAR (***)

4. Mongolia

5. Russia

6. Vietnam

(***) According to the Agreements on Exemption of Visa Requirements between Thailand and Hong Kong SAR and between Thailand and Macau SAR, all types of Thai passports including diplomatic and offcial passports shall be exempted from visa requirements for a visit of not exceeding 30 days to Hong Kong SAR and Macau SAR.

90 DAYS

1. Argentina

2. Brazil

3. Chile

4. Republic of Korea

5. Peru

Thanks, Lopburi. Mystery solved.