A BIS report submitted by the Committee on Payments and Market Infrastructures and the Markets Committee discusses potential implications of the introduction of central bank digital currency for payments, monetary policy, and financial stability.

From the executive summary

… CBDC is potentially a new form of digital central bank money that can be distinguished from reserves or settlement balances held by commercial banks at central banks. There are various design choices for a CBDC, including: access (widely vs restricted); degree of anonymity (ranging from complete to none); operational availability (ranging from current opening hours to 24 hours a day and seven days a week); and interest bearing characteristics (yes or no).

… Two main CBDC variants are … a wholesale and a general purpose one. The wholesale variant would limit access to a predefined group of users, while the general purpose one would be widely accessible.

… Traditionally, central banks have … This approach has, in general, served the public and the financial system well, setting a high bar for changing the current monetary and financial structure.

Wholesale CBDCs, combined with the use of distributed ledger technology, may enhance settlement efficiency for transactions involving securities and derivatives. Currently proposed implementations for wholesale payments – designed to comply with existing central bank system requirements relating to capacity, efficiency and robustness – look broadly similar to, and not clearly superior to, existing infrastructures. …

In part because cash is rapidly disappearing in their jurisdiction, some central banks are analysing a CBDC that could be made widely available to the general public and serve as an alternative safe, robust and convenient payment instrument. … analysing whether these goals could also be achieved by other means is advisable, as CBDCs raise important questions and challenges … the benefits of a widely accessible CBDC may be limited if fast (even instant) and efficient private retail payment products are already in place or in development.

… a central bank introducing such a CBDC would have to ensure the fulfilment of anti-money laundering and counter terrorism financing (AML/CFT) requirements, as well as satisfy the public policy requirements of other supervisory and tax regimes. … in some jurisdictions central banks may lack the legal authority to issue a CBDC … compared with the current situation, a non-anonymous CBDC could allow for digital records and traces, which could improve the application of rules aimed at AML/CFT.

Issuance of a CBDC would probably not alter the basic mechanics of monetary policy implementation, including central banks’ use of open market operations. … However, if flows into CBDC were to become large and not associated with offsetting declines in physical banknotes, as could be the case in times of financial stress, challenges could arise (such as a need to broaden the assets that the central bank can hold or take on as collateral).

CBDC could enrich the options offered by the central bank’s monetary policy toolkit, eg by allowing for a strengthening of pass-through of policy rate changes to other interest rates or addressing the zero lower bound (or the even lower, effective bound) on interest rates. … other more conventional tools and policies can to some extent achieve similar outcomes without introducing new risks and challenges (such as implementing negative interest rates on public holdings of a general purpose CBDC). And some of these gains might not arise without discontinuing higher denomination banknotes …

Implications are more pronounced for monetary policy transmission and financial markets, especially if a CBDC was to be designed as, or de facto became, an attractive asset. … could function as a safe asset comparable in nature to short maturity government bills. A general purpose variant could compete with guaranteed bank deposits, with implications for the pricing and composition of banks’ funding.

… A general purpose CBDC could give rise to higher instability of commercial bank deposit funding. Even if designed primarily with payment purposes in mind, in periods of stress a flight towards the central bank may occur on a fast and large scale, challenging commercial banks and the central bank to manage such situations. Introducing a CBDC could result in a wider presence of central banks in financial systems. This, in turn, could mean a greater role for central banks in allocating economic resources … It could move central banks into uncharted territory and could also lead to greater political interference.

For currencies that are widely used in cross-border transactions, all the considerations outlined above would apply with added force, especially during times of generalised flight to safety. …

… Further research …