Shopify Payments processing and conversion fees
When you sell in multiple currencies you're charged the regular Shopify Payments processing fee and a currency conversion fee.
You can find the fee values in your Terms of Service.
Shopify Payments fee
When you capture the payment for an order, you're charged a Shopify Payments fee to cover the cost of processing the payment. This fee depends on the type of credit card that is used (for example, the fee for a VISA card can sometimes be different from the fee for an American Express card) and the location where the credit card is registered:
Payment processing fees (Domestic) - The cost to process credit cards that are registered in the same country as your store.
Payment processing fees (Cross border) - The cost to process credit cards that are registered in a country that is different from your store's country.
When you use Shopify Payments, you aren't charged a transaction fee. If you deactivate Shopify Payments and enable an external payment provider, then you're charged a transaction fee for your orders going forward. This transaction fee is determined by your Shopify plan.
Conversion rate and fee
When you accept payment in a currency that is different from your payout currency, then a currency conversion occurs. The amount that you receive in your customer's local currency (also referred to as the presentment currency) is converted to your payout currency, and you're charged a currency conversion fee:
Currency conversion rate - The market rate at which one currency is exchanged for another. The conversion rate is not a fee (it's a mid-market rate, without any markup). For example, a conversion rate of USD/EUR
0.8788means that $1 USD is exchanged for €0.87 EUR.
Currency conversion fee - The fee that Shopify charges to convert currencies. This fee is charged when you capture payment. It's not charged when you issue a refund or when you receive a chargeback.