India

https://embassyofindiabangkok.gov.in/eoibk_pages/MTM0

• Valid passport, with at least 6 months validity, from the date of arrival.
• One application form. Two color photos (35mm x 45mm), not older than 3 months, taken against a white background.
• Covering letter mentioning data the name of the person responsible for bearing the expense of the trip, along with all particulars including hotel name, address and contact details.
• Air ticket (preferably showing departure after 5 working days of the Embassy).
• Hotel confirmation mentioning the names of all applicants/guests.
• Photocopy of credit card with original credit card statements of last 6 months.
• Last 6 months bank statement with original bank seal and a minimum balance of Rs.20,000/person.
• Original currency exchange slips of at least USD 500 (five hundred USD)/person/week with applicant’s name.
• Proof of accommodation – if intending to stay with relatives and friends, applicants must provide invitation letter along with a copy of their ID/passports. In case they are not Thai nationals, applicant must provide their working records in Thailand (e.g. work permit, letter from company they are working).

Philippines

https://philippines.siam-legal.com/

1. A visa is not required for Philippine passport holders visiting Thailand for short-term stay; 30 days. Have a passport valid for at least 6 months upon entry.
2. Entry via land or sea immigration checkpoints from neighboring countries allows for a 30-day stay, capped at 2 entries per calendar year. Present proof of exit within 30 days of arrival (60 days for those seeking extensions). Visitors must Show evidence of accommodation and adequate funds for the duration of their stay.

Vietnam

https://vietnam.siam-legal.com/

1. A visa is NOT required for Vietnamese passport holders visiting Thailand for a short-term stay: 30 days. Must have Vietnamese passport that is valid for six months beyond the period of the intended stay in Thailand.
2. Proof of onward travel (departure) from Thailand.