We just started a Monthly Subscription this year. We're now expanding it to non-US currencies (e.g., $AUD).
The challenge is that the amount the customer sees (in $AUD) will vary every month with the exchange rate. So on a $50/m $US subscription, an Australian might be billed $55.32 AUD, then $53.12 AUD, etc. That could really confuse a subscriber and cause them to question the charges.
I have one idea, but looking for other suggestions and feedback:
Charge less than $50 US so that they are always paying less than the list price.( So if it's $50 US/ $56 AU today we charge $45 US so they almost always pay less than the list price of $56 AU)
Have a note in the receipt that says:
Your Monthly Charge will vary slightly due to [Standard/public*] Exchange Rates.
The monthly charge appearing on your credit card statement will vary due to changing exchange rates but will usually be less than the list price.
We bill in $US but that charge is converted to your local currency and that exchange rate varies by month. We have discounted your price by $5 (US) so that, while your payment amount will vary with currency fluctuations, it means you'll normally pay less than the list price." (I'd word it more concisely).
*I need a better word here. Something that conveys that we're not just pulling the exchange rate out of thin air, and that it's the standard amount.