A strong start to the new year—are U.S. stocks seeing the “January Effect”?

(New York, Jan 7) Since markets reopened on January 2, global equities have delivered a steady—though not spectacular—performance. Citadel Securities believes this year’s “January effect” could be taking shape, as early-year flows and a broader participation in gains may be laying the groundwork for a more generalized rise in U.S. stocks.

The firm notes that January is often the strongest month for inflows, while cash-like balances in money-market vehicles remain elevated—potentially providing additional fuel for risk assets. These conditions align with the long-observed idea that U.S. equities tend to post stronger gains in January than in many other months.

Scott Rubner, Citadel Securities’ head of equities and equity-derivatives strategy, said that after the holiday closure, capital linked to pensions, year-end bonuses, and self-directed wealth management has been moving quickly into more passively allocated risk assets.

He added that this seasonal pattern is consistent with historical market behavior. In his analysis, the Nasdaq-100 has risen in January about 70% of the time since 1985.

Rubner also observed that flows appear to be expanding beyond the market’s most crowded trades, suggesting improving breadth, even as overall volatility remains relatively contained despite several potential catalysts this month.

He further argued that an AI-driven earnings cycle is increasingly spreading across sectors, strengthening market breadth and supporting the case for a more durable expansion in corporate profitability.