Currencies and multi-currency projects

Supported currencies

Mortar supports exactly five currencies, everywhere in the app — studio default currency, project currency, an item's native currency, the AI assistant, and currencies picked up automatically by the product scraper:

USD, EUR, GBP, AUD, NZD

Every currency picker in the app (project currency, an item's native currency when you add it manually, studio default currency, the "how do you price?" onboarding step) is a dropdown limited to these five — there's no free-text entry.

If you try to set a currency outside this list, you'll see:

Currency not supported — use one of USD, EUR, GBP, AUD, NZD.

Native currency vs. project currency

Items can be sourced in any of the five supported currencies — handy if you're buying from an overseas vendor. Each item stores its own native currency plus an exchange-rate snapshot taken when you added it. The project currency is the single currency everything gets converted into for budgets and invoices — set once per project, it's meant to be the currency your client actually pays in.

You (or the room owner) can refresh or manually override an item's exchange rate at any time, and there's a project-level "refresh all rates" action if you want to bring every item's rate up to date at once.

Changing a project's currency

Changing a project's currency (e.g. USD → EUR) automatically re-prices every item in the project against the new currency — this is expected, correct behaviour, not a bug. Every item's stored exchange rate is recalculated at the moment you make the change, so your budget and margin totals stay accurate rather than quietly drifting.

Two things can happen if something goes wrong mid-change:

No rate available for an item. If Mortar can't look up a current exchange rate for one of your items in the new currency, the whole change is rejected and nothing is saved — you'll see a message naming the specific item and the currency pair, e.g.:

Could not change the project currency to EUR: no FX rate available for "[item name]" (USD → EUR). No changes were made.

Try again shortly, or contact support if it keeps happening for the same currency pair.

Someone else edited an item at the same time. If an item's currency is edited by someone else at the exact moment you're changing the project's currency, your change is rejected with:

Items changed while updating the currency — please retry.

Just retry the currency change — nothing was left in a bad state, it's a clean rejection.

FAQ

Why did my budget total change after I changed the project's currency? Because every item was correctly re-priced against the new currency's exchange rate — that's the point of the change, and it's expected.

Why can't I set my project to CAD / JPY / AED / another currency I used to be able to pick? The supported list was narrowed to USD, EUR, GBP, AUD, NZD. If a project or item was already priced in a currency that's since been removed from the list, contact support — check with us before assuming any existing data was affected.

I got the "please retry" message — did I lose anything? No. That message means the change was rejected cleanly before anything was saved, specifically because of a conflicting edit. Just try the currency change again.