BoE's GBP Stablecoin Rules: A Flow Test of Market Viability

The Bank of England's proposed rules introduce a direct cost to liquidity and profitability. Systemic stablecoin issuers would be required to hold 40% of their backing assets as unremunerated deposits at the central bank. This is a pure flow drag, locking up capital that could otherwise earn a return and directly compressing the net yield available to the issuer.

The regime also imposes strict holding caps to limit scale. Individual users would be capped at £20,000 per stablecoin, while businesses face a £10 million per stablecoin limit. These ceilings are designed to prevent the widespread adoption that could threaten financial stability.

Viewed together, the 40% unremunerated deposit requirement and the rigid holding caps form a framework that appears intentionally restrictive. It aims to regulate the systemic scale it is meant to control by making large-scale operations costly and impractical.

Industry Pushback and the FCA's Contrasting Path

The regulatory split is now stark. While the Bank of England pushes a restrictive framework, the Financial Conduct Authority is actively building the market. In February, the FCA selected four firms to test stablecoin products in its sandbox: Revolut, Monee Financial Technologies, ReStabilise, and VVTX. This selection directly contradicts the BoE's proposed rules, which legal experts say would make a commercially viable market structurally impossible.

The Bank of England's Deputy Governor, Sarah Breeden, acknowledged the tension. She stated she was "disappointed" by the lack of constructive industry engagement over the proposals, which include a 40% unremunerated deposit requirement and strict holding caps. Yet she also affirmed the BoE is "genuinely open to other ways" of achieving its financial stability goals.

The current flow remains minuscule. At an approximate $12 million market capitalisation, the entire sterling stablecoin market is a rounding error compared to global leaders. The FCA's sandbox is a controlled experiment, but its success hinges on the BoE eventually aligning its systemic rules with the market it is trying to create. For now, the path forward is defined by a regulatory disconnect and a market still in its infancy.

Catalysts and Flow Implications: What to Watch

The immediate catalyst is the Bank of England's planned consultation on draft Codes of Practice next year. This phase will transform the current policy positions into binding rules. The outcome will be a definitive test: either the BoE lowers the 40% unremunerated deposit requirement to allow viable issuance, or it solidifies the flow barrier, making large-scale GBP stablecoins economically unfeasible.

Monitor the FCA sandbox results closely. The four selected firms-Revolut, Monee, ReStabilise, and VVTX-are building prototypes. Any successful, large-scale prototype emerging from the sandbox would directly challenge the BoE's restrictive regime. Its design would become a real-world benchmark against which the BoE's proposed rules must be measured.

The 40% unremunerated deposit requirement remains the most direct cost to issuer liquidity. Watch for any shift in the BoE's stance on this figure. A reduction would be the clearest signal that the central bank is prioritizing market viability over pure liquidity control. For now, the flow remains constrained by this single, costly metric.