Do Thai passport holders need a visa for Mexico?
By default — yes. Ordinary Thai passport holders must apply for a Mexican tourist visa at the Embassy of Mexico in Bangkok (~$48 USD, 5-15 working days). EXCEPTION: if you already hold a valid visa from the United States, Canada, United Kingdom, a Schengen state, or Japan (or an APEC Business Travel Card), you are exempt from the Mexican visa and may enter on the FMM at the airport for up to 180 days. Either way, the process is still much cheaper and faster than a US tourist visa ($185 / 8-12 month wait). Always confirm current rules with the Embassy of Mexico before traveling.