An exchange rate expresses one currency in terms of another. A published reference rate is not necessarily the rate available for a particular payment. The European Central Bank states that its reference rates are for information and discourages using them for transactions. Source: European Central Bank: euro reference exchange rates

Keep the direction of conversion clear

Use a fictional example to test your process: if the agreed rate were GBP 1 = EUR 1.20, EUR 120 would convert to GBP 100 before any separate charges. Divide by 1.20 for that direction. The figures are arithmetic illustrations, not a current rate or commercial offer.

Record the rate used in the quote

Save the currency pair, direction, rate source and time alongside the quoted amount. This allows a colleague to reproduce the calculation rather than substituting a newer rate and wondering why the total differs.

Check the provider’s actual conversion terms before collecting payment. If the quote includes an estimated equivalent, make that status clear and verify the final charge currency before the customer authorises the payment.

Written and updated by Travelgenix. Sources checked on 16 October 2026. Worked examples and checklists are editorial illustrations and recommendations, not customer results.