What is multi-currency support?

Multi-currency support lets your app accept payments and display prices in currencies other than AUD — for example, USD, GBP, EUR, or NZD. An Australian business selling software or services internationally needs to either charge in AUD (simple, but creates friction for overseas buyers) or in the buyer's local currency (better conversion, but more complexity).

There are two distinct concepts: presentment currency (the currency the customer sees and pays in) and settlement currency (the currency that arrives in your bank account). With Stripe, you can charge a customer in USD while settling in AUD — Stripe handles the conversion and remits AUD. The FX rate and any markup are factors in your net revenue.

Multi-currency also intersects with GST: supplies to overseas customers are generally GST-free under Australian tax law (exported goods and services), but the rules depend on the nature of the supply and the customer type. This needs to be reflected correctly in your invoicing.

When does your app need it?

• You're selling to customers outside Australia and want to reduce friction by charging in their local currency
• Your product is priced in USD (common for SaaS products targeting a global market) but you're an Australian entity
• You have a marketplace with buyers and sellers across multiple countries
• You want to display localised pricing on your marketing site and in-app based on the user's location
• Your enterprise customers require invoicing in their local currency as a procurement requirement
• You're expanding from an Australian-only product to a regional or global offering and want pricing to reflect local market rates

How much does it cost?

Adding multi-currency support typically adds 5–11 hours of development — roughly $1,000–$2,000 AUD.

At the lower end: displaying prices in a small number of fixed currencies using static exchange rates stored in configuration, with Stripe handling the actual currency conversion at checkout. The user selects their currency, prices are displayed using a stored rate, and Stripe charges in the selected currency.

At the higher end: live exchange rates fetched from a provider like OpenExchangeRates or Fixer.io (updated periodically and cached), a currency selector with geolocation-based defaults, correctly formatted currency display for each locale (e.g., "US$1,200" vs "£1,200" vs "1.200 €"), GST exclusion logic for international customers, and multi-currency invoice generation showing the charged currency and the AUD equivalent.

How it's typically built

Monetary storage: all amounts in the database are stored as integers in the minor unit of the currency (cents for AUD/USD, pence for GBP). This avoids floating-point rounding errors entirely. A currency column accompanies every amount column. Never store or calculate with floating-point values for money.

Exchange rates can be either static (manually maintained configuration, appropriate for a small number of currencies that don't change often) or live (fetched from OpenExchangeRates or Fixer.io, cached in your database and refreshed hourly or daily). Live rates mean prices fluctuate with the market — some businesses prefer fixed rates to avoid unexpected changes.

Stripe multi-currency: Stripe supports charging in 135+ currencies. You create a PaymentIntent specifying the currency and amount in that currency's minor unit. Stripe converts and settles in your account's default currency (AUD for Australian accounts). Be aware of Stripe's currency conversion fee (currently 2% for automatic conversion) — this affects your net margin on international sales.

Presentment vs settlement: display prices and generate invoices in the presentment currency. For reporting and internal accounting, always record the settlement amount in AUD alongside the presentment amount and exchange rate used.

GST on international sales: under Australian GST rules, most exported services to non-Australian businesses (B2B) are GST-free. Sales to overseas consumers (B2C) may attract GST under the digital services rules if your turnover exceeds the threshold. Confirm with your accountant what applies to your specific business model.

Questions to ask your developer

• Are monetary amounts stored as integers in the database? Floating-point storage for money leads to rounding errors. All amounts should be stored as integer minor units (cents).
• Static or live exchange rates? Static rates are simpler and more predictable; live rates are more accurate but prices can fluctuate. Which fits your pricing strategy?
• How is the customer's currency determined? Geolocation, explicit selection, or account setting — and can the user override it?
• How does GST interact with international customers? Confirm that tax logic correctly identifies exports and applies (or excludes) GST appropriately.
• How is multi-currency handled in invoices and reporting? Invoices should show the charged currency; financial reports need AUD equivalents for tax purposes.

---

See also: One-off payments · Invoicing and PDF generation · GST calculations · App cost calculator