What do I need to enter Thailand, just my passport?

To enter Thailand as a UK passport holder, you generally need just your passport and a return ticket, as UK citizens can stay for up to 60 days under the visa exemption policy. It is advisable to carry some cash (at least 10,000 baht or the equivalent) as proof of sufficient funds, although this is rarely checked. Additionally, having evidence of onward travel and an address in Thailand may be necessary, but usually, these requirements are not enforced strictly at immigration. Always ensure your passport has at least six months of validity remaining.