Stablecoin payments in September 2026: GENIUS Act proposals, MiCA, and what to test

Where the rules stand on 22 September 2026

United States. The GENIUS Act was approved on 18 July 2025 as Public Law 119-27. Section 20 says the Act takes effect on the earlier of "the date that is 18 months after the date of enactment" or "the date that is 120 days after the date on which the primary Federal payment stablecoin regulators issue any final regulations implementing this Act." A Federal Register search we ran on 22 September 2026 returned no final rule implementing the Act. Every document in the implementation track is still a proposed rule:

• OCC (Office of the Comptroller of the Currency) proposal for national banks, federal qualified issuers, and foreign issuers, published 2 March 2026, comments closed 1 May 2026 (2026-04089).
• FDIC (Federal Deposit Insurance Corporation) requirements and standards for FDIC-supervised issuers, published 10 April 2026, comments closed 9 June 2026.
• FinCEN and OFAC anti-money laundering and sanctions programme proposal for permitted payment stablecoin issuers (PPSIs), published 10 April 2026, comments closed 9 June 2026 (2026-06963).
• Treasury proposal on the section 3 limits on who may issue, offer, and sell payment stablecoins in the US, published 18 August 2026, comments open until 19 October 2026 (2026-16796).

A final rule issued on 22 September 2026 would start a 120-day clock ending after 18 January 2027, so the 18-month date now decides when the Act takes effect: 18 January 2027.

European Union. Titles III and IV of MiCA, Regulation (EU) 2023/1114, have applied to token issuers since 30 June 2024. Article 49(4) states that "the issuer of that e-money token shall redeem it, at any time and at par value, by paying in funds, other than electronic money", and Article 49(6) states that "Without prejudice to Article 46, the redemption of e-money tokens shall not be subject to a fee." Article 54(a) requires that "at least 30 % of the funds received is always deposited in separate accounts in credit institutions." For crypto-asset service providers (CASPs) that transfer e-money tokens, the EBA press release of 12 February 2026 confirms that the no-action transition period ended on 2 March 2026. Token transfers that qualify as payment services now need an authorisation under PSD2 (the second Payment Services Directive); the EBA Opinion lists conditions under which national authorities may let a CASP still awaiting that authorisation continue. CASP authorisation and the transfer of funds rules are on our MiCA testing requirements page.

The data point: stablecoin payments are dollar payments

The ECB Macroprudential Bulletin 33, published on 13 April 2026, states: "As of January 2026, euro-denominated stablecoins have a modest market capitalisation of around €450 million, up from €50 million at the beginning of 2024." The same article puts US dollar-denominated stablecoin market capitalisation at "around USD 300 billion". The euro figure counts only MiCA-authorised euro tokens listed in ESMA's interim MiCA register.

For stablecoin cross-border payments this ratio decides the flow. A payment from a euro account that settles through a dollar token to a recipient paid in a third currency makes two FX conversions, one at the on-ramp and one at the off-ramp, plus a token transfer between them. Each conversion is a place where a stale rate, a double-applied margin, or a rounding difference changes the amount the recipient gets. A dollar token also meets MiCA Article 58(3), which applies the Article 23 cap to e-money tokens "denominated in a currency that is not an official currency of a Member State": when use as a means of exchange within a single currency area exceeds 1 million transactions and EUR 200,000,000 per day on a quarterly average, the issuer must stop issuing that token and submit a reduction plan within 40 working days. A platform that routes euro-area payments through such a token needs a fallback route that has been tested before the issuer stops.

Why these rules change test scope

Redemption timing. The GENIUS Act, section 4(a)(1)(B)(i), requires "clear and conspicuous procedures for timely redemption". Proposed OCC 12 CFR 15.12(b)(1)(i) defines timely as "may not exceed two business days following the date of the requested redemption". Proposed 15.12(c)(1) extends the period to seven calendar days when redemption demands exceed "10 percent of its outstanding issuance value in a single 24-hour period", and 15.12(c)(4) requires notice to the OCC within 24 hours. The proposal does not define "business day", so the holiday calendar is a test input. MiCA has no window at all: "at any time".

Reserves. Section 4(a)(1)(A) requires reserves "on an at least 1 to 1 basis"; section 4(a)(1)(C) requires a monthly composition report with "the total number of outstanding payment stablecoins issued by the issuer"; section 4(a)(3) requires a monthly examination by a registered public accounting firm and a monthly CEO and CFO certification. Proposed OCC 15.11 bars new issuance while the issuer misses its reserve requirement, "except as necessary to facilitate a transfer of payment stablecoins from one distributed ledger to another and provided that the net outstanding issuance value does not increase."

Sanctions and lawful orders. Section 4(a)(6)(B) permits issuance "only if the issuer has the technological capability to comply, and will comply, with the terms of any lawful order", defined in section 2 as an order to "seize, freeze, burn, or prevent the transfer of payment stablecoins". The FinCEN and OFAC proposal applies the block, freeze, and reject capability to secondary market transactions, while "FinCEN is not proposing to require a PPSI as part of an AML/CFT program to monitor secondary market activity".

Travel rule. The same proposal applies the Recordkeeping Rule and Travel Rule of 31 CFR 1010.410(e) and (f) to PPSIs and amends the definition of transmittal order so that transfers of payment stablecoins are clearly covered. Recordkeeping starts at transfers of $3,000 or more.

What to test in a stablecoin payment flow

These are the checks we run on a stablecoin payment or remittance flow. The list is our practice; the rules above set the outcomes, and none of them prescribes these tests.

1. Redemption deadline by calendar. Compute the due date from the request timestamp, the issuer's time zone, and a stated holiday calendar. Assert the payout is initiated before the deadline, and assert the 10 percent trigger switches every open request to seven calendar days and raises the 24-hour OCC notice.
2. Par and fee. Redeem 1, 1,000, and 1,000,000 synthetic tokens. Assert the fiat amount equals the token amount at par, the fee equals the published schedule, and a fee change is refused inside the 7 days' notice of section 4(a)(1)(B)(ii). For an e-money token under MiCA, assert no fee applies outside Article 46.
3. Supply to reserve reconciliation. Sum on-chain total supply per deployed chain at a fixed block height, subtract tokens held in issuer treasury addresses, and compare the result with the internal ledger and with the "total number of outstanding" figure in the monthly report. The ledger reconciliation testing guide holds the break categories we use.
4. Cross-chain transfer. Burn on one chain, mint on another, and assert net outstanding value is unchanged at every intermediate state, including a mint that fails after the burn succeeded.
5. Freeze across every chain. Freeze a synthetic address on each deployed contract and assert that transfers from and to it fail, that a lawful order burn reduces supply in the reconciliation above, and that the platform ledger shows the frozen balance as unavailable.
6. Address screening before credit and before send. Screen counterparties against a synthetic list on deposit and on withdrawal. The sanctions screening false positive guide covers match thresholds.
7. Travel rule at the boundary. Send transfers valued at $2,999.99 and $3,000.00 after conversion from EUR, and assert the originator and beneficiary record is created at the conversion rate actually applied.
8. FX legs and settlement windows. Fix a rate at the on-ramp, delay the fiat off-ramp across a SEPA or ACH cut-off, and assert which rate the recipient gets and which party carries the difference. The FX rate application testing guide shows the rate-stamping assertions.

Custody, deposit confirmations, and travel rule messaging between CASPs are part of crypto exchange and wallet testing, and the failure patterns for exchanges that list stablecoins are on the crypto exchanges and wallets page.