Why Does MiCA Make Stablecoin Issuers Keep Reserves in Banks, and Why Does the ECB Want to Scrap It?

The EU's MiCA regulation requires a stablecoin issuer to keep at least 30% of its reserves as bank deposits, rising to 60% for significant tokens — lawmakers wanted to ensure fast redemptions. On September 22, 2026, the EU's central banks proposed scrapping that rule. Their argument: issuer money leaves a bank together with a wave of redemptions, so a stablecoin's problems become a bank's problems within hours.

What exactly does MiCA require of stablecoin reserves?#

The reserve rules sit in the MiCA regulation. As summarised in the European System of Central Banks (ESCB) response to the European Commission's consultation, at least 30% of reserve assets (60% for significant tokens) must be held as deposits at credit institutions. The rest can go into highly liquid instruments with minimal market, credit and concentration risk that can be sold quickly with little price impact. For e-money tokens, reserves must be in the same currency the token references.

Concentration limits come from the European Banking Authority's draft technical standards: no more than 25% of the reserve at a single systemically important bank, 15% at a large bank and 5% at any other. On top of that, an issuer's deposit at one bank may not exceed 1.5% of that bank's total assets. But as the ESCB notes, the Commission has not yet adopted these standards, so for now the deposit requirement itself is the only binding liquidity floor.

Why are issuer deposits flighty money for a bank?#

Retail deposits are fairly stable: customers rarely pull them all at once. An issuer's deposit behaves differently — it grows when tokens are minted and leaves when they are redeemed en masse. As FinTech Weekly puts it, in a run the issuer withdraws its deposits and stress in the stablecoin market reaches the banking system within hours.

That money is expensive for a bank. The ESCB points out that under bank liquidity rules such deposits may require a 100% outflow assumption unless they qualify for more favourable treatment. The bank then has to hold an equal amount of liquid assets and can barely lend against them. There is also the opposite problem: the rule can be met with term deposits that cannot be withdrawn on demand. The requirement is formally satisfied, yet the issuer has no more quick cash for redemptions.

What do central banks propose instead?#

The ESCB wants to replace the deposit percentage with liquidity buckets — minimum shares of reserves maturing within one and five working days. The starting point is the EBA's draft figures:

• daily bucket: at least 40% of reserves for significant tokens and 20% for others;
• weekly bucket, including the daily one: at least 60% and 30% respectively;
• for the remainder: maturity limits and counterparty diversification requirements.

For significant stablecoins the ESCB suggests more counterparties with lower limits each, and possibly an overall cap on how much deposit funding a bank may take from issuers. The central banks want to keep the ban on paying interest to holders. We explained why reserves sit in short-dated paper in our piece on Treasury bills, and the interest ban in stablecoins vs tokenized Treasury funds.

What does this change for a stablecoin holder today?#

Nothing yet. The Commission's consultation runs until September 30, 2026, and changing the rule requires amending MiCA itself; FinTech Weekly does not expect that before 2027. Redemption at par stays, and the ESCB supports keeping it. If the reform passes, European issuers such as the one behind EURC would likely hold fewer bank deposits and more short-term government paper and reverse repos.

What are the limits of this reform?#

• It is a position, not law. The Commission and EU lawmakers decide; final numbers may differ.
• Liquidity buckets do not remove risk. In a mass redemption the issuer must sell securities, pushing stress into government bond markets — a contagion channel the ESCB itself flags.
• Bank deposits are not risk-free either. If a bank holding reserves runs into trouble, redemptions can be delayed. Dropping the rule swaps one risk for another rather than eliminating risk.
• The percentages are minimums. An issuer can hold more liquidity than required; how safe a given token is shows only in its reserve reports.