Many central banks are considering whether to issue a new form of electronic money that would be accessible to the public. This new form is usually called a central bank digital currency (CBDC). Issuing a CBDC would have implications on the financial system and more broadly on the wider economy.

The effects of a CBDC on the banking sector, output and welfare depend crucially on the level of competition in the market for bank deposits. We show that when banks have no market power, issuing a deposit-like CBDC (that people can use like a debit card in transactions) would crowd out private banking. It would shift deposits away from the banking system, reducing bank lending.

However, in a more realistic scenario, when banks have market power in the deposit market, issuing a deposit-like CBDC with a proper interest rate would encourage banks to pay higher interest or offer better services to keep their customers. They can do so because they earn a positive profit. As a result, banks would attract more deposits and extend more loans. In this case, issuing a CBDC would not necessarily crowd out private banking. In fact, the CBDC would serve as an outside option for households, thus limiting banks’ market power, and improve the efficiency of bank intermediation.

We show quantitatively that the effects of a CBDC on lending, deposits, output and welfare can be sizable. We also analyze how different designs of a CBDC affect our results, including whether the CBDC is deposit-like or cash-like and whether the CBDC can be used to satisfy banks’ reserve requirements.