Multi-Currency

Overview

Axiomatic supports multi-currency accounting with automatic translation to each entity's functional currency. Foreign-currency journal lines carry both the original amount and the translated functional-currency amount with the applied exchange rate.

How It Works

1. Each entity has a functional currency (e.g. USD) set in its profile
2. When an event is posted in a foreign currency, the posting engine looks up the exchange rate for that date
3. Journal lines store both the original amount/currency and the translated functional amount/currency
4. Reports aggregate in the functional currency

FX Rate Resolution

When a rate is needed, the system tries three strategies in order:

1. Direct lookup — find a rate for the exact currency pair on the event date
2. Inverse lookup — if EUR→USD doesn't exist, use 1/USD→EUR
3. Triangulation via USD — convert through USD as an intermediate (e.g. GBP→USD→JPY)

Stablecoins (USDC, USDT, DAI, BUSD, EUROC) are automatically pegged 1:1 to their base fiat currency — no rate entry needed.

Managing FX Rates

Adding Rates via API

Single rate:

curl -X POST /api/fx-rates \
  -H "Content-Type: application/json" \
  -d '{
    "fromCurrency": "EUR",
    "toCurrency": "USD",
    "rate": "1.0850",
    "rateDate": "2025-06-15",
    "source": "manual"
  }'

Batch insert:

curl -X POST /api/fx-rates \
  -H "Content-Type: application/json" \
  -d '[
    { "fromCurrency": "GBP", "toCurrency": "USD", "rate": "1.2650", "rateDate": "2025-06-15" },
    { "fromCurrency": "JPY", "toCurrency": "USD", "rate": "0.00645", "rateDate": "2025-06-15" }
  ]'

Duplicate entries (same pair and date) are silently ignored.

Looking Up Rates

GET /api/fx-rates?lookup=true&from=EUR&to=USD&date=2025-06-15

Returns the closest rate on or before the requested date, with fallback to inverse and triangulation.

Posting Foreign-Currency Events

Post an event with a foreign-currency amount in the payload. The posting engine handles translation automatically:

POST /api/events
{
  "entityId": "your-entity-id",
  "type": "INVOICE_RECEIVED",
  "timestamp": "2025-06-15T00:00:00Z",
  "payload": {
    "vendor": "Euro Supplier GmbH",
    "amount": "10000.00",
    "currency": "EUR",
    "invoice_number": "INV-2025-042"
  }
}

The resulting journal lines will include:

Period-End FX Revaluation

At period end, monetary balances denominated in foreign currencies must be revalued at the closing exchange rate (per ASC 830 / IAS 21). This ensures your balance sheet reflects current exchange rates.

Preview Adjustments

Run a dry-run to see proposed adjustments before committing:

GET /api/fx-revaluation?entityId=...&bookId=...&asOfDate=2025-06-30

The preview shows:

• Which accounts have foreign-currency balances
• Current functional-currency balance vs. revalued balance
• The unrealized gain or loss per account

Execute Revaluation

POST /api/fx-revaluation
{
  "entityId": "your-entity-id",
  "bookId": "your-book-id",
  "asOfDate": "2025-06-30"
}

This creates a journal entry that adjusts each revalued account with an offsetting entry to your unrealized FX gain/loss accounts.

Prerequisites

Before running revaluation, ensure your entity has two account mappings configured:

These are typically mapped to accounts like "8100 Unrealized FX Gain" (Revenue) and "8200 Unrealized FX Loss" (Expense).

Currency Precision

The FX module uses currency-specific decimal precision for rounding: