Even though your registration site will be set to a specific currency, if your payment type is EventsAir Pay powered by Stripe, your attendee may be given a choice about what currency they pay in (for example, if the default currency on their credit card is different to the currency on the site).
This is called Adaptive Pricing, and the payment won't proceed until the attendee chooses which currency they want to pay in.
Stripe uses various session characteristics to work out which currency options to display, and automatically calculates the currency conversion(s). Site users see the original price and currency from the registration site, the price when converted to a different currency, what exchange rate was used, and what payment methods are supported (e.g. credit card, Klarna, AliPay, etc.)
They can still pay in the original currency you set, or choose another option.
Regardless of what currency the attendee pays in, the payment you receive matches the price you originally set, (in one of your settlement currencies). The card-issuing financial institution will levy any exchange rate costs on the cardholder.
In effect, the cardholder who chooses a different currency pays any exchange rate costs, in return for certainty about the amount they're paying (in their preferred currency).
EXAMPLE:
If the mid-market exchange rate is 1 Canadian dollar = 1 Australian Dollar and you have a 100 CAD item being sold to an Australian attendee, the Stripe-provided AUD price, including a 4% conversion fee, would be 1.04 AUD.
[1 CAD = 1 AUD, plus 4%]
The attendee will be presented with the option to pay 100 CAD or 104 AUD. Regardless of the customer’s currency selection, the merchant will receive 100 CAD (AUD 1.04), less applicable Stripe processing fees.
How this impacts refunds:
Stripe refunds your customer in the currency they paid in using the same exchange rate used in the transaction. You pay nothing to cover the refund and [assuming this is a full refund] your customer is refunded the original ticket price (converted to their currency). If exchange rates change dramatically in the meantime, this may result in a local currency refund amount that's larger or smaller amount than was originally paid. You should ensure your terms and conditions cover this. Refer to this article for more information.