Forex (Foreign Exchange, or FX) is the foreign currency exchange market. Every time an exporter converts dollars into baht, a tourist exchanges money for yen, or a foreign fund comes in to buy Thai stocks, the transaction takes place in this market.
How Big Is It?
According to a survey by the BIS (Bank for International Settlements) in April 2025:
- Trading volume was about $9.6 trillion per day, up 28% from 2022
- The US dollar was involved in 89% of all transactions
- Next were the euro (28.9%), the yen (16.8%) and the pound (10.2%) (all currencies add up to 200% because every transaction involves two currencies)
- The main trading centers are the United Kingdom (38%), the US, Singapore and Hong Kong, which together account for about 75%
Who Are the Players in the Market?
| Player | Role |
|---|---|
| Large commercial banks | Main traders; provide liquidity to the market |
| Central banks | Oversee the currency; sometimes intervene |
| Multinational companies, exporters, importers | Exchange money for actual trade and for hedging risk |
| Funds and institutional investors | Invest across borders; speculate |
| Retail investors | A very small share compared with the whole market |
Open 24 Hours, 5 Days a Week
Forex has no single central exchange. It trades through a network of banks around the world, so it is open continuously from Monday morning to Saturday morning Thailand time, divided into sessions based on financial centers.
- Asian session (Sydney, Tokyo, Singapore): morning to afternoon Thailand time
- European session (London): afternoon to late night
- American session (New York): evening to early morning
When the London and New York sessions overlap (roughly early evening to late night Thailand time), trading volume and volatility are usually at their highest.
Why Do Currencies Rise and Fall?
- Interest rate differentials: money flows to countries offering higher returns. Read Interest Rates and the Market
- Economic data, such as employment, inflation and GDP
- Trade balance and current account: a country that exports a lot has strong demand for its own currency
- Risk and fear: during crises, money tends to flow into the dollar, yen and Swiss franc, which are seen as safe
- Politics and policy, such as import tariffs and elections
In Thailand, trading Forex with platforms that solicit the public involves important legal issues you need to know about. Read Forex in Thailand: Legal Issues You Need to Know
Sources
For education only, not investment advice. Figures change over time, so check official sources before making decisions.