The Bank of Thailand, with 11 financial associations, is tightening rules against "grey money" and illegal flows. Cash withdrawals over 5 million baht already need reporting; from October 2026 cash deposits over 5 million baht will require the source of funds. Online gold trades over 2 kg or 10 million baht must be reported, foreign currency buying is capped at 800,000 baht per person per day, and transfer limits will vary by risk group. If your business handles large cash deposits, FX exchange or gold purchases, prepare source-of-funds documents and expect banks to ask more questions.