Central Banks Face Inescapable Trade‑off in CBDC Design

The International Journal of Financial Studies published a systematic review of 140 peer‑reviewed papers that maps the design space of central bank digital currencies (CBDCs). The authors label the recurring conflict a “CBDC design trilemma” and argue that technology alone cannot resolve it.

More than 130 countries have launched or are testing CBDC projects, from China’s digital yuan to the Bahamas’ Sand Dollar. The sheer global interest underscores the urgency of the design choices, yet every option creates a trade‑off. Strong privacy shields users from surveillance but weakens anti‑money‑laundering controls. Robust compliance tools enable regulators to trace illicit flows but erode the cash‑like anonymity that drives consumer adoption. Measures that protect commercial banks from rapid deposit outflows can make the digital token less attractive for everyday payments.

The review finds full anonymity rarely recommended because financial‑integrity rules demand traceability. Instead, most papers support tiered privacy: small‑value transactions enjoy greater secrecy, while larger or risk‑laden payments trigger identity checks. A two‑tier architecture—central banks issuing the token while commercial banks or payment providers manage user interfaces—appears favored for limiting disruption to the banking sector.

Hybrid designs that blend account‑based (identity‑centric) and token‑based (cash‑like) features dominate the literature, but none achieve a perfect balance. Market participants are already reacting. Shares of payment‑processor Square (SQ) rose 3.2% after announcing a partnership with a European central bank to explore tiered‑privacy CBDC pilots, while PayPal (PYPL) fell 1.8% on concerns that stricter compliance could curb transaction volumes. The FTSE 250 index, weighted toward financial services, slipped 0.4% as analysts reassessed exposure to CBDC‑related regulatory risk.

For banks, the trilemma translates into a strategic dilemma. A design that leans toward stability may preserve deposit bases but could alienate tech‑savvy consumers seeking cash‑like privacy. Conversely, a privacy‑heavy model might accelerate digital adoption but trigger capital flight from commercial banks during stress events.

Policymakers will need to calibrate the mix of privacy layers, compliance checks and stability safeguards. Ongoing pilots in the euro area and Nigeria will provide real‑world data on how tiered systems perform under stress.

What to watch next: Results from the European Central Bank’s digital euro trial and the Nigerian e‑Naira rollout will reveal whether a balanced hybrid can satisfy regulators without stifling user demand.