How long can a Russian passport holder extend their stay in Thailand with a 30-day stamp?

A Russian passport holder who entered Thailand with a 30-day stamp can typically apply for an extension of stay. The maximum extension allowed is generally 30 days, allowing for a total stay of up to 60 days. However, it's also advisable to consider traveling to a neighboring country to obtain a new tourist visa, which can extend the stay for a longer duration, such as 60 days or more.