If you buy from overseas suppliers, your purchase orders are in their currency and your books are in yours. Stockroom keeps both: the supplier sees the price you agreed, and you see what it costs you at home.
Set your supplier's currency once
Open a supplier and set Currency. Every new purchase order for that supplier starts in it, so you never pick it per order. Leave it blank and the supplier uses your store currency. Setting it is also what puts the Currency box on your purchase orders: a store that buys in a single currency never sees it, and it appears in the Cost summary once any supplier or order of yours is in another currency.
The exchange rate lives on the purchase order
A foreign-currency PO shows an Exchange rate with a daily reference rate already filled in, so there is no empty box to guess at. It reads like 1 EUR = 0.855 GBP - your currency per one unit of theirs.
Click Set rate to type the rate you actually settled at. Your bank takes a spread and customs use their own published rate, so the number on your invoice is rarely the market mid.
Use latest rate puts the current reference rate back.
The rate shows Your rate when you set it and Reference rate with its date when it came from the daily feed, so you can always tell which is which.
The rate is editable while the PO is a draft and locks when you mark it as ordered. That is deliberate - it stops last month's orders re-pricing themselves every time rates move.
What you see on the order
The Cost summary shows the order in the supplier's currency, with Total in your currency beside it. Your purchase order list does the same, and the Incoming value tile converts each order at its own rate rather than adding up currencies that do not belong together. Orders with no rate yet are counted separately, so the figure is never quietly wrong.
Charges in another currency
Freight, customs and brokerage are often billed in a different currency from the goods, and by someone other than your supplier. Add the cost with Add shipping or Add adjustment and pick its Charge currency: the order's, your own, or any other. For a currency that is not listed, choose Other and type its code. The Charge currency box appears once you buy in more than one currency, the same as the order's Currency box. Until then, every charge is in the order's currency.
For example, a store in Canada buys goods from a supplier who prices in euros, pays a freight company in US dollars, and pays customs in Canadian dollars. The goods use the order's exchange rate, the freight uses the US dollar rate, and the customs charge needs no rate at all.
Each charge converts at its own rate. Any currency that is neither the order's nor yours gets one rate for the whole order, shown in the Cost summary as a line like 1 USD = 1.37 CAD. Click Set rate or Edit to type the rate you recorded in QuickBooks or Xero, so your landed cost matches your books. If you leave it, Stockroom uses the latest reference rate.
A charge in any currency other than the order's is marked Not on supplier copy. It does not print on the PO PDF, it carries no supplier tax, and it stays off the supplier's bill in QuickBooks or Xero.
A charge in the order's currency that somebody else bills you for can stay off the supplier's bill too: untick Billed by this supplier when you add it.
When any charge is off the supplier's bill, the Cost summary shows Supplier's invoice total alongside the full total, so you can check it against their invoice.
Every charge still counts toward landed cost, including custom splits. Record the off-bill ones against whoever billed you for them in your accounting app, because Stockroom does not create a separate bill for them.
Product costs and reporting
When you mark a foreign PO as ordered, or receive it, Stockroom converts each cost at that order's rate before updating your Shopify cost per item. Cost updates are always your choice and always previewed first.
When you receive, Rate for this delivery starts at the order's rate. If you paid the invoice at a different rate, type it there, and that delivery's costs and landed cost use it. The rate is written onto the receipt and the converted costs are stored with it. Your cost of goods reports read those stored figures, so changing the order's rate later never moves history you have already reported on.
If you find out the right rate after receiving, open the order's History, click Edit costs on that delivery, and change the rate in Correct received costs. Stockroom recalculates that delivery's landed costs and notes the change in the history.
Good to know
Stockroom never guesses. With no rate on the order, cost updates are offered but not performed, and the order tells you a rate is needed rather than inventing one.
The pre-filled rate is a daily reference rate. It is close, but it is not your bank's rate - if the exact figure matters to you, type the one from your invoice.
Totals are never blended across currencies. Reports that span several currencies show each one separately.
Documents your supplier receives stay in their currency throughout - the PO PDF and the email show the price you agreed with them and nothing else.
Related: Keep your product costs current when you order and Landed cost: what your stock really costs.