The SONIA market continued to operate smoothly as policymakers examined longer settlement hours and possible changes to benchmark administration. The Bank of England published the latest SONIA Stakeholder Advisory Group minutes on October 15, covering its September 25 meeting and conditions observed during the third quarter.

Key Insights

  • Unsecured overnight sterling transactions averaged about £55 billion a day, while the SONIA-Bank Rate spread stayed close to 1.9 basis points.
  • Money market funds received roughly £15 billion of net inflows during 2026 and increased their overnight allocations.
  • Industry participants favored keeping SONIA’s 9 a.m. publication time even as the U.K. considers near-24/7 settlement.

SONIA market remains stable

The Bank of England said the unsecured overnight market remained stable, with daily volume near £55 billion. The spread between SONIA and Bank Rate held around 1.9 basis points, indicating that overnight sterling funding continued to track the policy rate closely.

Money market funds drew approximately £15 billion of inflows during the year and placed more assets overnight. Repo markets still showed month-end volatility, but the group said the spikes were smaller than those recorded a year earlier. The result is consistent with a broader picture of steady U.K. activity, including the latest U.K. GDP data.

Longer settlement hours affect the SONIA market

The central bank’s consultation on expanding RTGS and CHAPS operating hours could change when sterling transactions settle and when benchmark data become complete. One option would close settlement at 6 p.m. and reopen at 8 p.m., while future weekend access would require decisions on which transactions belong to each business day.

Participants preferred to preserve SONIA publication at 9 a.m. rather than move the benchmark later. A later release could disrupt contracts and operational routines built around the existing timetable, while weekend operation could create additional questions about rate calculation and reporting.

What investors should watch

ICE expanded trading hours for SONIA and gilt futures on July 6, and the group noted greater participation from non-U.K. clients. That wider access may deepen liquidity, but investors should monitor whether activity shifts across time zones as settlement hours expand.

The Bank of England and HM Treasury are also reviewing data-collection powers, adding a regulatory dimension to benchmark oversight. That work sits alongside changes to U.K. clearing collateral rules and global rate expectations, including the Reserve Bank of Australia’s inflation outlook.

Source: Bank of England, SONIA Stakeholder Advisory Group minutes, published October 15, 2026.

Elsy Kanana is a financial and cryptocurrency journalist at FusionMarketNews, covering digital assets, blockchain technology, financial markets, and emerging fintech trends. Her reporting focuses on market movements, regulatory developments, and on-chain analytics, delivering clear, data-driven insights to readers worldwide.