my $19 charges are landing as $17.42 - where does the other 8% go before it hits my bank

The fixed fee per transaction is the lever you control most easily and nobody talks about it.

Twelve monthly charges of $19 cost you twelve fixed fees. One annual charge of $190 costs you one. At US standard rates that is roughly $3.30 of fixed fees saved per customer per year, on top of the failed payment recovery and the churn difference. On a small base that is not nothing - at 60 customers it is a couple of hundred dollars a year for offering a plan you were probably going to offer anyway.

Second lever: your average ticket. The percentage cost of a $9 plan is brutal and the percentage cost of a $49 plan is much more comfortable. If you have been thinking about a higher tier, the fee structure is quietly arguing for it.

8.3% blended with mostly international customers on a $19 ticket is normal. Raise the price before you optimise the fee. A dollar on the price is worth more than every fee negotiation available to you at this size.

For context on the alternative: a merchant of record takes a materially bigger cut, roughly in the five percent plus a fixed fee territory depending on provider and options, and rates have changed recently enough that you should read the current page rather than trust a number in a forum post. What you are buying for that difference is sales tax and VAT handled entirely.

So your 8.3% is not obviously bad. It is what direct processing plus cross border traffic costs. The question is whether the compliance work you are doing yourself is worth the delta.

Build it up piece by piece and it stops being mysterious. Using the published US standard rates as the example, a domestic card online is 2.9% plus 30 cents. On $19 that is about 55 cents plus 30, so 85 cents, which is already 4.5% and not 3% - the fixed fee is a third of your cost at this ticket size.

Then international cards add a further percentage on top of the base rate, and if a currency conversion is involved there is another percentage again. Both of those are listed on the public pricing page. With 60% of customers abroad, a blended rate somewhere in the six to seven percent range is entirely expected.

The last chunk is on the way out. Getting money from your processor balance into your own bank in a different currency has its own spread, and it usually does not appear as a line item anywhere in your dashboard. That is where the remainder of your 8.3% is hiding.

Also count the things that never appear on the fee line. Refunds where you keep paying the fee, failed payments that retry and succeed later, disputes and their fees, and any tax you are collecting and remitting that passes through your account and makes revenue look larger than it is.

I keep two numbers now: gross charged and cash landed in the bank. The gap between them is the number I actually manage, and I look at it monthly rather than per transaction, because per transaction it is invisible and monthly it is obvious.