Who is the 'Water Seller' Behind the New Stablecoin Banks?

A practical test of the fiat channels behind five new stablecoin banks.

Written by: Paymentscan

Compiled by: Luffy, Foresight News

All top stablecoin banks offer some form of fiat accounts: U.S. accounts, IBANs, or other personalized banking information similar to traditional banks.

Although the user experience seems similar, the underlying implementation logic of these products is completely different.

The vast majority of new banks do not build their own banking infrastructure but rely on a few suppliers to open accounts, process bank transfers, and complete foreign exchange transactions. From supported currencies, foreign exchange spreads to KYC review rules, everything is determined by these underlying suppliers behind the scenes.

We aim to determine whether these differences will actually affect users. To this end, we have sorted out the banking infrastructure of five mainstream stablecoin banks: RedotPay, EtherFi, KAST, Avici, and Gnosis Pay.

We confirmed the underlying service providers, compared the dollar fees and currency coverage published by the platforms, and actually deposited and withdrew tens of thousands of euros to determine the actual foreign exchange rates and transfer times.

Overview of New Bank Infrastructure Status

We compared euro payment channels through practical tests, depositing and withdrawing 5000 euros from each new bank. Except for a few exceptions, deposits usually arrive within minutes, while withdrawals take several hours.

After adjusting for exchange rate fluctuations, a complete "deposit-withdraw" process, including the total cost of foreign exchange spreads and various fees, ranges from a minimum of just 2 dollars to a maximum of 130 dollars.

For dollar payment channels, we compared the official fee schedules. These fees are mainly composed of fixed costs for ACH, wire transfers, and SWIFT, with some additional percentage fees. Completing the full process of depositing and withdrawing 5000 dollars through ACH incurs total fees ranging from 2 to 16 dollars.

We identified which underlying providers these new banks use based on various clues, including branded KYC domain names, specified bank account details, and in some cases directly consulting the new bank's customer service.

Note: All test transactions occurred between July 21-23. Exchange rates fluctuated during the testing period, and we adjusted some data by up to 40 basis points, standardizing it to the starting exchange rate (5000 euros = 5704.7 dollars).

Complete Test Results

During the testing process, we recorded the fees, transfer durations, and whether accounts were opened in real names for each platform. We also found that leading new banks generally have rich local withdrawal capabilities: they can complete withdrawals using local clearing networks for the corresponding currencies but do not provide users with dedicated bank account information.

### RedotPay

RedotPay relies on OpenPayd to provide virtual accounts in euros and pounds (not supporting dollars). Opening any of these virtual accounts incurs a fee of 7 dollars, while the other tested platforms are free to open.

The 5000 euro test deposit was supposed to arrive within minutes, but due to additional manual review, the funds ultimately took about 60 hours to become available.

RedotPay has a separate euro balance, and deposited funds are not automatically converted into stablecoins. When we manually converted, we received 5591.01 USDC, with an effective fee of 113.69 dollars (2%), which is the highest level in this test, likely an additional revenue source set by RedotPay.

Withdrawing 5000 euros, the system deducted 5722.58 USDC, with a fee of 17.88 dollars (about 0.3%). Notably, the withdrawal was processed by another service provider, Red Dot Payment, taking less than 1 minute.

RedotPay's local withdrawal function covers a wide range, including over 30 currencies in Latin America, Asia, and Africa. The fees for this function generally range from a few dollars depending on the currency; among them, the withdrawal fee for dollars can reach up to 50.50 dollars. We additionally tested the withdrawal of Singapore dollars, with funds sent by partner iSend.

### EtherFi

EtherFi has a relatively complete banking channel, offering virtual accounts in dollars, euros, Brazilian reais, Mexican pesos, Colombian pesos, pounds, and UAE dirhams, and supports withdrawals in five other currencies (Canadian dollars, Hong Kong dollars, Honduran lempiras, Israeli shekels, and Indian rupees). This coverage is provided by two service providers: Bridge and Due.

The euro virtual account provides two independent IBANs, allowing users to choose whether to deposit as EURC or USDC.

We deposited 5000 euros through Due's virtual account, choosing to receive USDC to test foreign exchange costs, ultimately receiving 5695.12 USDC, with an effective fee of 9.21 dollars (0.16%). Using the USDC balance to withdraw 5000 euros, we deducted an equivalent of 5714.04 USDC, with a fee of 9.34 dollars (0.16%).

In the early stages of testing, the interface also displayed the euro account provided by Bridge, but this entry later disappeared from the page. We retrieved an earlier email receipt for a 5 euro deposit and withdrawal, confirming that Bridge's bidirectional foreign exchange spread exceeds 0.5%. Multiple verifications confirmed that other euro virtual accounts provided by Bridge also have this situation. This explains why EtherFi now defaults to providing Due's bank account information.

For dollar transactions, regardless of which underlying service provider, the fee standards are consistent: 0.1% for deposits and 0.2% for withdrawals; plus fixed network fees: ACH 0.5 dollars, SWIFT/wire transfer 20 dollars.

### KAST

KAST connects with two service providers: Bridge mainly handles dollar accounts; Noah manages euro accounts and supports withdrawals in over 20 other currencies.

KAST only provides dollar balances, and a 5000 euro deposit is automatically converted to dollars, arriving at 5704.43 dollars, with a fee of nearly 0, only 0.27 dollars. The withdrawal page shows a SEPA fee of 2 dollars, with the first three transactions per month being free. However, the actual foreign exchange spread exceeds 1%, resulting in a total deduction of 5762.78 dollars for the withdrawal, with a comprehensive cost of 59.29 dollars.

KAST significantly subsidizes dollar deposit and withdrawal fees: ACH fee 2 dollars, wire transfer deposit 15 dollars, SWIFT deposit 30 dollars; no percentage fees for deposits and withdrawals. Normally, withdrawals would incur a 0.5% fee, but this is currently in a waived state.

### Avici

Avici's dollar and euro virtual accounts are provided by Iron (which was acquired by MoonPay in 2025). Both euro and dollar deposits and withdrawals uniformly incur a fixed fee of 1 dollar / 1 euro (wire transfer 15 dollars), with no percentage fees.

Avici does not provide euro balances; a 5000 euro deposit is directly credited to the dollar account, arriving at 5702.81 dollars, with a deduction of 1 euro fixed fee, resulting in an exchange rate equivalent to the market mid-price at that time.

The withdrawal process is the same, with the system deducting 5705.99 dollars. The Avici team stated that regardless of the transaction size, there are no foreign exchange fees for deposits and withdrawals.

This platform performed the best overall in terms of fee rates in this test. However, Iron's KYC partner, Sumsub, has an extremely complicated and time-consuming due diligence process. To unlock the initially deposited 5000 euros, we submitted over ten personal documents over a week, including bank and exchange transaction records, tax documents, business registration files, rental contracts, etc.

### Gnosis Pay

Gnosis Pay is a new banking infrastructure, with products like Rebind, Picnic, and Zeal (the subjects of this test) built on it. It only supports euro virtual accounts, with Monerium as the service provider.

Deposits are directly received as Monerium-issued EURe stablecoins, with zero fees, and withdrawals are also completely free. For a fair horizontal comparison, we also calculated the cost of converting EURe to USDC on-chain:

• 5000 EURe → 5705.39 USDC (an increase of 0.69 dollars)
• 5713.76 USDC → 5000 EURe (cost 9.06 dollars)

What Insights Can We Draw?

On the surface, the user experience of most stablecoin banks appears highly similar: local bank accounts, fast transfers, and mutual conversion between fiat and stablecoins. However, the actual underlying costs depend entirely on the service providers behind them and the new banks' choices regarding fees or subsidies.

The testing summarized some common phenomena:

• The fee range for platforms with dollar and euro virtual accounts is 0-0.3%, with significant subsidies generally provided during the deposit phase.
• The processing fees for dollar transfers via ACH, wire transfers, and SWIFT are mostly directly passed on to end users.
• Euro SEPA transfers generally have no fixed fees, but the differences in foreign exchange spreads are enormous, ranging from 0% to 2%.

The disparity in foreign exchange spreads exceeded expectations. Especially for KAST and RedotPay, the fees charged are significantly higher than their peers, compressing the profit margins for the upper-level new banks. Although we cannot fully verify, we suspect that the higher fees of KAST and RedotPay are part of the platforms' own revenue rather than the costs of the underlying service providers.

In terms of coverage, we found that the virtual accounts of the aforementioned suppliers support the following currencies:

In terms of local withdrawal capabilities, OpenPayd, Due, and Noah support the most currencies, each covering dozens of currencies.

When inquiring about the reasons for these emerging banks' choices of these banks, we learned that compliance and banking relationships are the main considerations:

• EtherFi, which uses Bridge and Due, stated that the core considerations are compliance, product experience, clearing links, and fees.
• Kolo, which has just integrated Due, also mentioned that the MiCA license and stringent compliance capabilities are the core selling points of the service providers.

Postscript

The above service providers cover the vast majority of new banks, but there are still many builders in this space. Companies frequently mentioned but not directly contacted during this test include: Dakota, Modern Treasury, Bastion, Unlimit, and Tazapay.

The competition in the new banking underlying clearing track is becoming increasingly fierce, and we look forward to a year from now when users can have more choices in rates and services.