Currency Reference Rates vs Dealing Rates: Why They Differ
A currency reference rate is an informational value for a particular date or period. It is not a promise that a bank, card issuer or exchange will offer the same price. A displayed conversion is only as current and applicable as the underlying rate.
Worked example · Updated
Check the direction of the rate
If a rate is expressed as target units per one base unit, multiply the base amount by that rate. As an illustration only, an amount of 100 multiplied by a rate of 0.90 gives 90 target units. This is not a current market quote.
For the opposite direction, use the corresponding inverse rate rather than multiplying by the same number. Rounding an inverse before calculation can slightly change the result.
Why your transaction may differ
The exchange spread, fixed fees, percentage fees, settlement time and card conversion rules can all affect the final amount. A page receipt time is also different from the date of the rate itself.
In the currency tool, inspect the reference date after pressing Convert. A background refresh does not mean the underlying source has published a newer reference value.
Use reference figures carefully
The linked tool opens with 100 USD and EUR as the target. Press Convert when the reference information is ready. Confirm any financial decision with the relevant transaction provider and account for all charges.
Rate history is context, not a prediction. Missing dates or delayed updates should not be interpreted as unchanged market conditions.
| Item | Illustrative value |
|---|---|
| Base amount | 100 |
| Target units per base unit | 0.90 |
| Before charges | 90 |
| Fixed target-currency fee | 2 |
| After that illustrative fee | 88 |
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