Converting KRW 10,000,000 for U.S. Stocks: 95% vs. 0% Exchange Rate Discounts Make a Fee Difference of Approximately KRW 94,000
When converting KRW 10,000,000 into U.S. dollars to invest in U.S. stocks, if the standard currency exchange spread is 1%, the cost difference between exchange rate discounts of 95% and 0% is approximately KRW 94,000. However, this is a calculation example using the same reference exchange rate, and the actual difference varies depending on each brokerage's exchange rates and discount conditions.
As of 2026-10-23, when comparing currency exchange costs, you should check not only the discount rate but also the standard spread, exchange hours, and actual exchange rate applied.
How Much Can an 95% Exchange Rate Discount Reduce Fees?
An 95% exchange rate discount does not mean that 95% of the total amount being exchanged is deducted. It means that 95% of the brokerage's standard currency exchange spread is discounted.
The currency exchange spread is the difference between the reference exchange rate and the actual exchange rate applied when purchasing U.S. dollars.
The following comparison assumes a standard spread of 1%.
| Category | 0% Exchange Discount | 95% Exchange Discount |
|---|---|---|
| Standard spread | 1% | 1% |
| Discount rate | 0% | 95% |
| Spread after discount | 1% | 0.05% |
| Simple calculation based on KRW 10,000,000 | KRW 100,000 | KRW 5,000 |
The KRW 100,000 and KRW 5,000 figures in this table are simple comparison values calculated by multiplying the principal amount being exchanged by the spread after the discount.
Therefore, the simple calculation produces a difference of KRW 95,000.
However, when converting the entire KRW 10,000,000 into U.S. dollars, a higher applied exchange rate means receiving fewer dollars. Accounting for this difference produces a slightly different result.
How Many Dollars Would You Actually Receive at USD 1 KRW 1,400?
Let's assume a reference exchange rate of KRW 1,400 per USD 1 and convert the entire KRW 10,000,000.
The exchange rate is an assumed value used for the calculation and does not represent the real-time exchange rate on 2026-10-23.
We also assume a standard spread of 1% and no additional costs.
| Category | 0% Discount | 95% Discount |
|---|---|---|
| Reference exchange rate | KRW 1,400 | KRW 1,400 |
| Applied spread | 1% | 0.05% |
| Exchange rate applied when buying dollars | KRW 1,414 | KRW 1,400.70 |
| Dollars received | Approximately USD 7,072.14 | Approximately USD 7,139.29 |
| Currency exchange cost relative to the reference rate | Approximately KRW 99,010 | Approximately KRW 4,998 |
Calculated by the author. Figures have been rounded for display, and the actual amount exchanged and dollars received may vary depending on the brokerage's processing methods.
Calculated cost difference when exchanging KRW 10,000,000
Approximately KRW 94,012
Applying the 95% exchange rate discount results in receiving approximately USD 67.15 more.
In this calculation, the actual cost is the amount obtained by converting into Korean won the difference between the dollars that would be received at the reference exchange rate and the dollars received after accounting for the spread.
Therefore, the simple calculation result of KRW 95,000 and the approximately KRW 94,012 result based on the actual currency conversion outcome come from different calculation methods.
Why the Fee May Not Be KRW 5,000 Even With an 95% Exchange Rate Discount
The discount rate alone does not determine the actual cost of exchanging currency.
The amount you pay after the discount depends on the size of the standard spread.
For example, if a brokerage with a standard spread of 0.5% and another brokerage with a standard spread of 1% both offer an 95% discount, their spreads after the discount would be 0.025% and 0.05%, respectively.
This means that actual costs can differ by a factor of two even with the same 95% discount.
The time of the currency exchange also matters.
According to Toss Securities' official fee information, based on a standard spread of 1%, an 95% discount applies from 9 a.m. to 3:30 p.m. on Korean business days, while an 50% discount applies at other times, including weekends and public holidays.
Under these conditions, the spread after the discount is 0.05% during regular hours and 0.5% outside regular hours.
Applying these rates directly to KRW 10,000,000 produces simple cost estimates of KRW 5,000 and KRW 50,000, respectively, showing that costs can vary significantly depending on the time of day.
However, operating hours and discount conditions differ among brokerages, so these terms do not apply universally.
Are U.S. Stock Trading Commissions Separate From Currency Exchange Fees?
When investing in U.S. stocks, currency exchange fees and stock trading commissions must be calculated separately.
Currency exchange fees are costs incurred when converting Korean won into U.S. dollars or converting U.S. dollars back into Korean won.
Trading commissions, on the other hand, are charged based on the transaction amount when buying or selling U.S. stocks.
For example, if the commission for buying U.S. stocks is 0.1% and the Korean won equivalent of the actual stock purchase amount is KRW 10,000,000, the trading commission would be KRW 10,000 under a simple calculation.
This is separate from the costs incurred during currency conversion.
Trading commissions and other charges may also apply when selling U.S. stocks.
Therefore, when comparing brokerage fees, it is advisable to check both buying and selling commissions rather than focusing only on currency exchange discounts.
What Should You Check Before Exchanging KRW 10,000,000?
Before actually exchanging currency, check the following items in your brokerage app.
1. Check the standard spread for converting funds into U.S. dollars.
2. Check the exchange rate discount applicable to your account and the expiration date of the benefit.
3. Check whether exchange rate discounts differ between regular and after-hours currency exchange.
4. Check the estimated amount of U.S. dollars you would receive when entering KRW 10,000,000.
5. If comparing different brokerages, compare their estimated dollar amounts at approximately the same time whenever possible.
The most direct way to compare offers is to check how many dollars you would receive for the same KRW 10,000,000.
Even if the discount rate is higher, the final amount of dollars received may differ because of differences in reference exchange rates or standard spreads.
Services that allow you to place U.S. stock orders directly in Korean won also require separate consideration. The exchange rates and discount conditions for manual currency conversion may differ from those for automatic conversion.
Are There Costs Both When Converting Into Dollars and When Converting Back Into Korean Won?
A spread may apply not only when purchasing U.S. dollars but also when converting those dollars back into Korean won.
However, because the exchange rate discount, exchange rate, and amount exchanged may differ between the initial purchase and subsequent sale of dollars, simply doubling the initial currency exchange cost would not be accurate.
If you continue holding the proceeds from selling U.S. stocks in U.S. dollars, you may not immediately incur the cost of converting them back into Korean won.
Conversely, if you want to withdraw funds in Korean won, you should check the exchange rate applied when selling U.S. dollars.
Investing in U.S. stocks can also generate foreign exchange gains or losses due to fluctuations in the Korean won–U.S. dollar exchange rate, in addition to changes in stock prices.
Receiving a substantial currency exchange discount does not reduce losses caused by unfavorable exchange rate movements.
If you plan to invest KRW 10,000,000 in U.S. stocks, compare the currently applied exchange rate and the final amount of dollars you would receive before pressing the exchange button. Even when converting the same amount, the dollars actually available for investment can differ.
※ This article is provided for informational purposes to help readers understand market conditions and does not constitute an investment recommendation for any particular stock or asset. You are responsible for your own final investment decisions and their outcomes.