Special Purpose Depository Institution (SPDI)
A Special Purpose Depository Institution is a Wyoming state bank charter for institutions that take deposits and custody digital assets without lending out customer fiat. It is a bank charter with restricted powers — not a national charter, not automatically FDIC-insured, and with no guaranteed Federal Reserve access.
Also called: Wyoming SPDI · special purpose depository institution
Wyoming created the SPDI charter in 2019 for businesses that wanted bank status for digital-asset custody and payments without running a lending book. The defining condition is full reserving: the Wyoming Division of Banking states that SPDIs must have their customer deposits of fiat currency at all times backed 100% or more by unencumbered liquid assets, and that as fully-reserved banks SPDIs are prohibited from making loans with customer deposits of fiat currency. The statute carves out custodial and fiduciary transactions, and permits digital-asset lending undertaken on customer instruction.
The other three facts are the ones that get misstated. An SPDI is a state charter, not a national bank charter. It is not required to obtain FDIC insurance, though it may apply — so an SPDI deposit is not insured by default. And access to Federal Reserve services is a separate question that has been litigated: in the Custodia case the Tenth Circuit held that a Reserve Bank may decline a master account to an institution that is statutorily eligible, denied rehearing en banc in March 2026, and a petition to the Supreme Court followed.
What the charter is genuinely good for is a regulated, examined, fully-reserved home for customer fiat and digital assets under one supervisor, in a state with a developed digital-asset statute.
In practice
An SPDI is a bank without being a full-service bank. Do not assume FDIC insurance, do not assume direct Federal Reserve settlement, and do not treat historical litigation summaries as the current position — the master account question has moved more than once and is not finally settled. Verify the specific institution's permissions rather than the charter's reputation.
Example
A business moves customer fiat to an SPDI expecting insured deposits and same-day Fed settlement. It gets a fully-reserved, state-examined deposit at an institution that may hold neither FDIC insurance nor a master account, and whose dollar settlement runs through a correspondent like anyone else's.
Commonly confused with
| Term | How it differs |
|---|---|
| Bank Charter | An SPDI is one kind of state bank charter with restricted powers. A national charter from the OCC is a different instrument with different powers and a different regulator. |
| Trust company | Several states charter trust companies that custody digital assets. Their powers, reserving rules and deposit-taking authority differ from an SPDI's. |
| Reserve Requirement | An SPDI's 100% reserving is a charter condition set by Wyoming. The federal reserve requirement — a monetary policy ratio — has been zero since March 2020 and is a different thing entirely. |
See also
- Bank CharterA bank charter is the authorisation that makes an institution a bank — granted in the United States either by a state banking department or by the federal Office of the Comptroller of the Currency. Deposit insurance and access to Federal Reserve services are separate approvals, not things the charter brings with it.
- Reserve RequirementA reserve requirement is the proportion of its deposits a bank must hold rather than lend out. In the United States that proportion has been zero since 26 March 2020, so the textbook money-multiplier story no longer describes how US bank lending is constrained.
- Crypto CustodyCrypto custody is holding someone else’s crypto-assets, or the means of access to them, in a way that lets you move them. The test is control in fact — who could move the balance without the customer’s cooperation — not how the service describes itself in its terms.
- Master AccountA master account is an account held directly at a Federal Reserve Bank. It gives its holder settlement in central bank money and direct access to US payment systems, instead of reaching them through a commercial bank that holds an account on its behalf.
- Proof of ReservesProof of reserves is published evidence that an issuer or exchange holds the assets it says it holds — typically a third-party verification report on holdings as at a single date, sometimes paired with a cryptographic exercise letting customers check that their own balance was counted. It is not an audit.
- BitLicenseNew York’s dedicated license for virtual currency business activity, granted by the New York State Department of Financial Services under rules in force since June 2015. It is separate from a New York money transmitter license, and a firm that also moves fiat currency generally needs both.
Go deeper
Regulatory information checked: 23/Sep/2026