What You Need
Use the supplier quote's currency/amount and a planning rate with explicit units, date and source. This is a budget-assumption calculation, not a live-rate lookup or an accounting translation instruction. Keep provider fees separate and UNKNOWN until actual evidence exists.
Steps
- Write the rate as the amount of one currency per unit of the other.
- Multiply or divide so the source currency cancels and budget currency remains.
- Test the result using the exact reciprocal before rounding for display.
- Recalculate using two explicitly labeled alternative planning rates.
- Record excluded fees, accounting treatment and required human decisions separately.
This sequence tests a conversion; it does not reproduce the budget narrative worksheet's field list.
Output: Fictional Three-Row Test
The fictional training-services quote is 12,000 EUR. Planning memo FX-1, dated September 15, 2026, assumes 1 EUR =1.10 USD. Its two sensitivity scenarios, also labeled in that dated fictional memo, use 1 EUR =1.18 USD and 1 EUR =1.04 USD. None is a live quote or forecast.
| Fictional FX-1 scenario, Sep 15, 2026 | Conversion | Change from base |
|---|---|---|
| Base:1.10 USD per EUR | 12,000 EUR x 1.10 USD/EUR =13,200 USD | Base |
| Higher:1.18 USD per EUR | 12,000 x 1.18 =14,160 USD | +960 USD;960 /13,200 x 100 =7.27% rounded |
| Lower:1.04 USD per EUR | 12,000 x 1.04 =12,480 USD | -720 USD;720 /13,200 x 100 =5.45% rounded |
Assumption statement:12,000 EUR is budgeted at 13,200 USD using fictional FX-1's September 15, 2026 rate 1 EUR =1.10 USD; bank fees remain UNKNOWN, and neither sensitivity nor accounting treatment is approved here.
For the reciprocal check,1 /1.10 =0.909090...EUR per USD, displayed as 0.909091. Using the exact reciprocal,13,200 USD /1.10 USD-per-EUR returns 12,000 EUR. The rounded reciprocal gives approximately 12,000; do not treat the rounding residue as a new rate or cost.
Exception: Wrong Direction
Dividing 12,000 by 1.10 gives 10,909.09 after rounding. That operation does not cancel EUR with a USD-per-EUR quote to produce USD. It understates the correct 13,200 by 2,290.91. Correct the direction and preserve the reason; do not fix the number by relabeling its currency.
Human Decision
The budget owner decides whether to hold 13,200 or request a currency margin under the actual funder rules, which are not supplied. The accounting owner determines later framework-specific translation. Obtain actual provider rates/fees before a transfer; this planning exercise establishes no recipient amount or bank charge.
Source Scope
ECB's October 30, 2026 reference-rate page explains quote direction and warns rates are informational, not transaction prices. FRS 102's September 2024 edition, section 30, is a UK/Ireland accounting framework, separate from this planning calculation. HMRC CFM12070 (collection updated August 27, 2026,UK tax context) describes bank/documented transaction-rate sources; it does not mandate these record fields. Charity Commission funds guidance (January 5, 2011,England/Wales), ASIC MoneySmart (September 17, 2026,Australia) and FCAC (October 29, 2026,Canada) inform FX exposure and actual fee/rate questions within their scopes. No source supplies this invented rate or accounting instruction. Checked November 1, 2026.