If you ever carry a large amount of cash into a Thai bank branch, expect more questions from Sunday 1 November 2026. The Bank of Thailand (BOT), the country's central bank, said on 26 October that new rules for cash-related transactions take effect on that date. Under BOT Notification No. 57/2569, banks and other financial institutions must apply enhanced due diligence when a customer's cash transactions at a branch add up to 5 million baht or more within the same day.
Enhanced due diligence, often shortened to EDD, is the closer level of checking banks use for higher-risk business. In practice the BOT says it can mean asking where the money came from, what the transaction is for, or for documents that support it, depending on how risky the bank judges the customer and the transaction to be.
What is covered
The headline change applies to cash deposits that reach 5 million baht in one day. The BOT has also widened the rule to other cash transactions at or above the same level: depositing cheques or drafts whose source is unclear, exchanging Thai baht banknotes, paying cash to have a cheque or draft issued, buying, selling or exchanging foreign currency, and paying insurance premiums, investment products or financial derivatives in cash.
Banks must report transactions that look unusual or do not fit a customer's normal pattern to the BOT. The central bank also says institutions should keep things reasonably convenient for customers and deal quickly and fairly with anyone affected.
What is not covered
The rules apply only to transactions carried out at bank branches. The BOT says they do not affect customers using electronic channels, so ordinary app and online banking sits outside this measure. Thairath's English-language summary of the notification adds that the extra checks do not mean such transactions will be refused; banks may simply need more information before going ahead.
Why it matters for expats
Few residents handle 5 million baht in cash, but the threshold is not out of reach for some. Settling a property purchase, paying for a car, topping up an insurance or investment policy, or changing a large sum of foreign banknotes over the counter could all reach it, and the BOT counts the total for the day rather than each transaction on its own. If you expect to make a large cash transaction at a branch, it makes sense to have your passport, the paperwork behind the payment and a clear explanation of where the money came from to hand. Your own bank can tell you exactly what it will ask for.
The BOT frames the measure as part of its push against so-called grey money and fraud, and links it to the Bangkok Blueprint for Fraud-Resilient Financial Services, an initiative it has promoted with the International Monetary Fund and the World Bank Group. The Nation and the Bangkok Post reported the same scope and the 1 November start date.