# Introduction - Exchange Adjustments

When you invoice in one currency and get paid in another, or hold a foreign balance across a period end, the exchange rate moves and the difference has to go somewhere.

**Video coming soon:** Revaluing foreign balances at period end.

Exchange adjustments are where it goes.

![The Exchange Adjustments screen listing one adjustment with columns for Date, Reference#, Currency, Exchange Rate, Status, Gain/Loss and Notes.](https://www.sorviai.com/help/exchange-adjustments/exchange-adjustment-list.png)

*Each run records the rate it used, which is what makes the resulting gain or loss explainable.*

## Realised differences

These happen by themselves. You invoice 1,000 EUR when EUR is worth one thing, the customer pays when it is worth another, and the two translations into your base currency do not match. SorviAI Finance posts the difference when the payment is recorded.

1. **Invoice raised**: Rate on the invoice date
2. **Payment received**: Rate on the payment date
3. **Difference posted**: Realised gain or loss

> **Note:**
>
> **You do not post realised differences yourself**
>
> They are calculated and posted automatically at settlement. This module is for the unrealised ones.

## Unrealised differences

At a period end, foreign balances still outstanding are worth a different amount in your base currency than when they were raised. Revaluing them is what makes your balance sheet true on the reporting date, and it is a deliberate step you run.

Nothing runs it for you, which is why a foreign balance that looks wrong at period end is almost always a revaluation nobody remembered.

## Do you need any of this

If every customer, vendor and bank account is in your base currency, no. There is no foreign balance, nothing to revalue and no difference to post. The moment one customer is in another currency, all of it applies.