Foreign exchange on card purchases: explain the rate assumption
A careful guide to documenting the exchange-rate date, fee and transaction amount without promising a final cost.
Editorial status: needs review. A careful guide to documenting the exchange-rate date, fee and transaction amount without promising a final cost. This is general information, not personal financial advice.
What to record
A foreign-currency card purchase should be explained with the transaction currency, conversion assumption and any disclosed fee rather than an unexplained AUD estimate.
Before relying on a rate, fee, eligibility rule or complaint pathway, check the linked official source and the current provider terms. Record the date checked, the exact assumption and the next review date.
A practical checklist
- Identify the decision the reader is making.
- Compare like-for-like fields and keep unknown information visible.
- Save the official document or page used for each material claim.
- Use the internal link to Southern Ledger methodology and send corrections through our corrections page.
Disclaimer
This article is general information only, not personal financial advice. Current issuer terms, regulator guidance and the reader’s circumstances control.
Sources checked
- Choosing a credit card — MoneysmartSupports: A foreign-currency card purchase should be explained with the transaction currency, conversion assumption and any disclosed fee rather than an unexplained AUD estimate. · consulted 2026-08-11
- Interest rates — Reserve Bank of AustraliaSupports: The surrounding costs and conditions should be recorded from current official documents before a reader compares products. · consulted 2026-08-11
General information only, not personal financial advice. Check current issuer terms, regulator guidance and your own circumstances before acting.