Cards and stablecoins: one app, two ways to get paid

Yes, you can take a bank card and a stablecoin from the same FiatFlex app, with no second terminal and no second contract. They do not travel the same road, nor carry the same fees: the card goes through a Stripe account opened in your name and costs 0.50% in FiatFlex commission, plus the Stripe fees charged to that account, 1.4% + €0.20 on Tap to Pay; the stablecoin arrives in a Solana wallet we operate on your behalf, which is custody, and costs nothing to receive, while converting it into euros costs 1% in commission plus a flat bank fee of 0.30 USD per SEPA transfer. On €100 the total is €2.10 for a card tap and €1.26 for EURC converted.

This article sets out who does what, where your money sits at each step, and which of the two rails to choose for a given sale. The detailed fee figures are in our pricing; here the point is the mechanism.

Exactly who does what

This is the part most often misread, so here it is without hedging.

Stripe acquires the card payment. The payment lands in a Stripe account opened in your own name, created during your signup. Stripe's fees are charged to that account, they do not pass through us, and you find them on your Stripe statement.

Bridge converts the stablecoin into euros and sends the SEPA transfer to your bank account.

FiatFlex operates the wallet and the app: the payment links, Tap to Pay, the record of what came in, the conversion request, the history.

FiatFlex is not a bank, not a payment institution and not an electronic money institution. The regulated parties in the chain are Stripe and Bridge. The wallet we operate is custody: FiatFlex holds those funds on your behalf, and that wallet is not a bank account.

Where your money sits, step by step

On the card rail, the money never passes through a FiatFlex balance. Your customer's payment lands in the Stripe account opened in your name. Stripe charges its processing fees there, our 0.50% commission is taken there as a platform fee, and the balance is paid out to the bank account you registered. The funds are therefore held by the regulated payment partner, never by us.

On the stablecoin rail, your customer's payment lands in the Solana wallet opened for your account. We operate that wallet, and FiatFlex holds those funds until you ask for a conversion or a withdrawal. That is custody, not self-custody, and we will never write it up as anything else. The funds stay there as long as you ask for nothing. When you trigger a conversion, Bridge converts into euros and sends the SEPA transfer to your bank.

We publish no timing, at any step. Our banking partner has confirmed none to us, and announcing an unconfirmed timing would be a promise, not information.

Cards: 0.50% to us, the rest to Stripe

Our commission on a card payment is 0.50%. Stripe's fees are added on top, for a consumer card issued in the European Economic Area: 1.4% + €0.20 on Tap to Pay, 1.5% + €0.25 on a payment link.

All in, that gives €2.10 on €100 with Tap to Pay, €2.25 on €100 through a payment link, and €0.39 on a €10 ticket with Tap to Pay. Look hard at that last figure: €0.39 on €10 is 3.9% of the ticket, against 2.10% on €100. On a small ticket the fixed €0.20 weighs as much as the percentages do, and any price list quoted as a bare percentage hides precisely that line.

Moving your card balance to your bank costs nothing.

Stablecoins: free to receive, 1% to convert

Receiving a stablecoin is free. We accept USDC and EURC on Solana.

Converting into euros is not free, and you are the one who triggers it, when you decide to. Nothing converts on its own. It costs 1% commission on the amount converted, plus a flat bank fee of 0.30 USD per SEPA transfer, plus 0.50% of spread on USDC only, since EURC converts at par. That bank fee is flat: one per transfer, whatever the amount moved. The exact amount is shown to you before you confirm.

On €100 received in EURC, the conversion therefore costs €1.26 in total. On the same €100 received in USDC, the 0.50% spread adds €0.50 on top of that.

Which rail, and when

The honest reading is this: on a €10 ticket converted on its own, a stablecoin costs roughly the same as a contactless card payment: the commission is only €0.10 in EURC, but the flat bank fee of 0.30 USD lands in full, against €0.39 for the tap, and in USDC the spread puts it a little higher. That is not a flaw in the product, it is the flat 0.30 USD per transfer crushing a small amount.

The stablecoin becomes clearly cheaper in two situations.

The ticket is large. At €100, €1.26 in EURC against €2.10 on card: the gap is real, because the flat fee is diluted in a bigger amount.

Conversions are grouped. Ten payments of €10 in EURC, converted in a single operation, make €100 converted and cost €1.26 in total. The same ten sales taken on Tap to Pay cost €3.90. The flat bank fee is paid once instead of ten times.

Hence the practical rule: let the stablecoin balance build up, then convert in one go. Converting every €10 sale one at a time means paying the same fixed bank fee ten times over. We go through that mechanic in converting stablecoins into euros.

The card, for its part, keeps an advantage the stablecoin will never have: every one of your customers has one. Choosing a rail is not a matter of principle, it depends on the customer in front of you.

What each rail cannot do

A card payment can be disputed. A dispute costs €20 per dispute received, and €20 more if you contest it, that second €20 returned to you if the decision goes your way. On a refund, we return our commission on the refunded amount, but Stripe does not return its processing fees.

A stablecoin payment does not sit inside that mechanism: once confirmed on Solana it is final, and there is no equivalent dispute procedure. That is an advantage for you, and it is also why a customer has no automatic recourse: refunds are a commercial decision you handle yourself, the way you would for a cash payment. The trade-off is real in the other direction too: a transfer sent to the wrong address does not come back.

Where this is available

We are launching in France: both rails described here are for merchants in France, and Tap to Pay on iPhone is available there at launch.

Frequently asked questions

Do I need two contracts to accept cards and stablecoins?

No. You open a FiatFlex account, and your Stripe account is created in your own name during signup. Both ways of getting paid live in the same app, with the same history.

Is the conversion into euros automatic?

No, and that is deliberate. You keep the stablecoin balance for as long as you want and trigger the conversion yourself. That is exactly what lets you group conversions and pay the flat 0.30 USD only once.

Do I have to manage a crypto wallet myself?

No. The wallet is operated by FiatFlex, which makes it custody. You handle no recovery phrase, no third-party software and no address to copy across.

What does accepting a stablecoin cost if I never convert?

Nothing. Receiving is free, with no subscription and no signup fee. Fees only appear when you convert into euros and request the transfer.

USDC or EURC?

EURC if you invoice in euros: it converts at par, without the 0.50% spread. On €100 converted that is €1.26 in EURC, and €0.50 of spread more in USDC. The detail is in USDC or EURC, which to choose.

To try both rails on your own amounts, download the app. The detailed terms are in our terms and conditions, and the full schedule is on the pricing section.