> ## Documentation Index
> Fetch the complete documentation index at: https://docs.duitpos.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Exchange Rates

> Set how many units of one currency equal one unit of another, as of a specific date.

An **Exchange Rate** says "1 unit of *From Currency* is worth this many units of *To Currency*, as of this date." When you create a document in a foreign currency (e.g. a Purchase Invoice in USD, but your base currency is MYR), the system looks up the most recent applicable rate and **locks it in at submit time** — so the amount posted to your accounting books is fixed and never silently changes later, even if you add a newer rate afterward.

<Frame>
  <img src="https://mintlify.s3.us-west-1.amazonaws.com/duitpos-128fe424/images/retail-exchange-rate.png" alt="Exchange Rates list showing USD to MYR at 4.70" />
</Frame>

## Exchange Rate Fields

| Field             | Required | Description                                                                  |
| ----------------- | -------- | ---------------------------------------------------------------------------- |
| **From Currency** | Yes      | The currency being converted from, e.g. `USD`                                |
| **To Currency**   | Yes      | The currency being converted to, e.g. `MYR`                                  |
| **Rate**          | Yes      | How many units of *To Currency* equal 1 unit of *From Currency*, e.g. `4.70` |
| **As Of Date**    | Yes      | The date this rate takes effect                                              |

<Warning>
  Rates are **not automatically inverted**. Adding `USD → MYR` at `4.70` does **not** mean the system can figure out `MYR → USD` on its own (that would be `1 / 4.70`). If you ever create documents in both directions, add both rate rows explicitly.
</Warning>

<Tip>
  When a document needs a rate, the system uses the **most recent rate on or before the document's posting date** — not necessarily the newest one in the list. Keep your rates up to date if you transact in foreign currency regularly, e.g. update weekly or daily.
</Tip>

## Create an Exchange Rate

<Steps>
  <Step title="Go to Retail → Exchange Rates">
    Under Retail — Masters.
  </Step>

  <Step title="Click New Rate">
    Choose From Currency, To Currency, the Rate, and the date it takes effect.
  </Step>

  <Step title="Save">
    The rate is now available to any document posted on or after this date, until a newer rate is added.
  </Step>
</Steps>

## Frequently Asked Questions

<AccordionGroup>
  <Accordion title="What happens to a document's rate if I later add a newer exchange rate?">
    Nothing — the rate is locked into the document at the moment it's submitted. Adding a new rate afterward only affects documents submitted after that point.
  </Accordion>

  <Accordion title="Where does the currency gain/loss on payment show up?">
    If a payment is made on a different date (and therefore a different rate) than the original invoice, the difference posts automatically to the **FX Gain/Loss** account — you don't need to calculate or post it manually. See [Payments](/retail/payments).
  </Accordion>
</AccordionGroup>

## Related

<CardGroup cols={2}>
  <Card title="Currencies" icon="coins" href="/retail/currency">Register the currency first</Card>
  <Card title="Purchase Invoices" icon="file-input" href="/retail/purchase-invoices">Create a foreign-currency invoice</Card>
  <Card title="Payments" icon="wallet" href="/retail/payments">See FX gain/loss on settlement</Card>
  <Card title="Overview" icon="layout-dashboard" href="/retail/overview">Back to the module overview</Card>
</CardGroup>