Some clients outside of Canada may have noticed an extra charge (around 1-4% of the total charge) added to their Wild Apricot subscription fees. Wild Apricot does not charge these fees. Since 2005 both Visa and Mastercard added a "cross-border assessment" surcharge on some purchases made outside the credit card's country of origin. See:
Since this is an optional extra charge, some card issuers simply tack on this fee to the cardholder, and it will even appear as a payment to Wild Apricot on the credit card statement. This is an Issuer Assessment applied directly by your Credit Card Issuer, this is not charged by Wild Apricot.
Canadian customers are assessed GST / HST on top of the subscription fees specified on the pricing page.