Currency guide
Historical Exchange Rates for Accounting
Historical rates can support reconciliations, invoices and research, but the correct rate for an accounting or tax purpose depends on the applicable policy and jurisdiction.
Record the complete observation
Keep the base and quote currencies, requested date, actual published date, source and calculation. If the requested day has no publication, document the policy used to select another date.
Daily, monthly and official rates
A daily market reference, a monthly government accounting rate and an organization's internal policy can produce different valid results for different purposes. Do not substitute one without checking the governing requirement.
A practical audit trail
Export or retain the source table and note any rounding.
- Identify the applicable accounting or tax rule.
- Preserve the provider and actual rate date.
- Use a consistent direction and rounding policy.
- Have a qualified adviser review material compliance decisions.
Example: a weekend invoice date
If an invoice is dated Sunday and the provider publishes only working-day observations, document the requested date, the actual rate date selected under the applicable policy, the source and the rounding used.
Practical comparison
| Rate type | Typical purpose | Selection rule |
|---|---|---|
| Daily reference | General comparison | Published observation date |
| Monthly official rate | Jurisdiction-specific reporting | Authority's published month |
| Organization policy rate | Internal accounting | Documented company policy |
Common misconceptions
- The nearest available rate is always legally acceptable.
- A monthly tax rate and a daily reference rate are interchangeable.
- The cache-read date can replace the provider's rate date.
Practical steps
- Identify the governing accounting or tax rule.
- Record requested and actual published dates.
- Preserve the source table or export.
- Document direction, calculation and rounding.
Related resources
Sources and review
Data source: Official references listed below. This educational guide does not publish a current exchange-rate quote.
Last data update: Not applicable to this educational guide.
Last editorial review:
Report an errorThis guide provides general currency reference information. It is not financial, tax, accounting, legal, investment or trading advice.