What is Overnight Fee in Forex? A Complete Guide for Thailand Traders (2026)

What Exactly is an Overnight Fee?

In forex trading, every currency pair involves borrowing one currency to buy another. When you hold a position overnight, you pay or receive interest based on the difference between the central bank rates of those two currencies. This is the overnight fee, or swap. For Thailand traders, this means trading pairs involving the Thai Baht (THB) will have swap rates influenced by the Bank of Thailand's policy rate.

How Overnight Fees Work in Practice

Every forex broker sets a daily rollover time, usually 5:00 PM New York time (which is 4:00 AM or 5:00 AM Thailand time depending on daylight saving). If you keep a position open past this time, the swap is applied. The fee can be positive (you earn) or negative (you pay). For example, if you buy a currency with a higher interest rate against one with a lower rate, you may receive a credit. In Thailand, many experienced traders trade USD/THB or EUR/THB, and the swap rate reflects the gap between the US Federal Reserve or ECB rates and the Bank of Thailand rate.

Why It Matters for Thailand Traders

Thailand traders who use local brokers often have accounts denominated in THB. This means swap charges are converted to THB, affecting your account balance directly. Additionally, with the Bank of Thailand's interest rate decisions in 2026-2026, swap rates can shift. For example, if the BOT raises rates, holding short THB positions may become more expensive. Experienced traders in Thailand often factor swap costs into their long-term strategies, especially for carry trades where they aim to earn positive swaps.

For Thailand traders, the local context is critical. Payment methods like PromptPay allow instant deposits, which helps you quickly add funds to manage margin or close positions before rollover. Bank transfers are common for larger deposits, while Skrill offers an alternative e-wallet option. However, the overnight fee itself is not affected by the deposit method. What matters is that you can monitor your positions and act swiftly using these local tools.

SEC Thailand regulates forex brokers operating in the country. While they do not set swap rates, they require brokers to disclose all fees transparently. Thailand traders should always verify that their broker is licensed by SEC Thailand or a reputable international regulator. This ensures that if there are disputes over swap charges, you have legal protection. Many Thailand traders prefer brokers that offer swap-free accounts or transparent swap schedules, especially those using PromptPay for quick funding.

1. Check the swap rate for your pair
   Before opening a trade, review the broker's swap schedule. For Thailand traders, focus on pairs like USD/THB, EUR/THB, or GBP/THB. Note whether the swap is positive or negative for your position direction.
2. Know the rollover time in Thailand time
   The rollover occurs at 5:00 PM EST, which is 4:00 AM or 5:00 AM Thailand time depending on daylight saving. Plan to close positions before this time if you want to avoid the fee.
3. Calculate the cost in THB
   If your account is in THB, multiply the swap in pips by your position size. For example, a 1 lot USD/THB position with a -10 pip swap costs you 10 THB per day.
4. Use PromptPay for quick adjustments
   If you need to add margin or close a position to avoid a negative swap, PromptPay allows instant deposits. This is especially useful for Thailand traders who trade actively.

Overnight fees are different from commission fees, which are one-time charges per trade. For Thailand traders, a broker might charge 0.01% commission per trade, while overnight fees recur daily. Another concept is swap-free accounts, which waive overnight fees but often have wider spreads or administrative charges. Experienced traders in Thailand compare these costs: a day trader might prefer lower spreads and accept swaps, while a swing trader might seek a swap-free account to avoid daily charges. Use comparebroker.io to see which option suits your strategy.

When you open a forex trade, you are essentially borrowing one currency to buy another. The overnight fee reflects the interest cost of that borrowing. For Thailand traders, if you buy USD/THB, you are borrowing THB (paying the Bank of Thailand rate) and buying USD (earning the US Fed rate). The difference, plus the broker's markup, becomes the swap. For example, if the BOT rate is 2.5% and the Fed rate is 5.5%, the net interest difference is 3% annually. Your broker converts this to a daily pip value. In THB terms, a 1 lot standard trade might have a swap of -10 THB per day if you are short, or +10 THB if long. The exact amount depends on the broker's markup and current rates.

Example 1: Long USD/THB
Assume the US Fed rate is 5.5% and BOT rate is 2.5%. You buy 1 standard lot (100,000 units) of USD/THB. The interest difference is 3% per year in your favor. Your broker charges a 0.5% markup, so net is 2.5% per year. Daily swap = (2.5% × 100,000 USD) / 365 = approximately 6.85 USD, converted to THB at current rate (say 35 THB/USD) = 239.75 THB per day. You receive this amount.

Example 2: Short USD/THB
If you sell 1 lot USD/THB, you are borrowing USD (paying 5.5%) and buying THB (earning 2.5%). Net difference is -3%, plus broker markup of 0.5%, so -3.5% annually. Daily swap = (-3.5% × 100,000 USD) / 365 = -9.59 USD, or -335.65 THB per day. You pay this fee.

SEC Thailand (The Securities and Exchange Commission, Thailand) regulates forex brokers that offer services to Thai residents. While they do not set overnight fee rates, they mandate that brokers disclose all fees transparently in the account agreement. This includes swap rates for all currency pairs. Thailand traders should ensure their broker is listed on the SEC Thailand website. If you encounter undisclosed fees or unfair swap charges, you can file a complaint with SEC Thailand. This regulatory oversight provides a layer of protection, but you must still do your due diligence. Always read the terms regarding swaps, especially for exotic pairs like THB crosses.

• Plan around Bank of Thailand announcements: Interest rate decisions by the BOT directly impact THB swap rates. Stay updated on monetary policy meetings.
• Use a swap calculator: Many brokers provide tools to calculate overnight fees in THB. Use them before entering a trade.
• Consider carry trading: Experienced Thailand traders sometimes aim for positive swaps by buying high-yield currencies against THB. But be aware of currency risk.
• Monitor rollover times: Set alerts for 4:00 AM Thailand time to decide whether to hold or close positions.
• Compare brokers: Different brokers have different swap markups. Compare rates on comparebroker.io before choosing.

Understanding overnight fees is essential for Thailand traders who want to manage their forex costs effectively. By knowing how swaps work, when they are applied, and how to calculate them in THB, you can make informed decisions. Use local tools like PromptPay for quick funding and always check your broker's swap schedule. For more detailed comparisons of brokers and their swap rates, visit comparebroker.io. Start by reviewing your current broker's swap policy, and consider switching if fees are too high. Remember, every pip counts in your journey to becoming a profitable trader.