Russell 2000 Surges Over 21% in H1 2026, Posts 35-Year Record for Small-Cap Performance

Russell 2000 small-cap index (the major benchmark for U.S. small-cap stocks) delivered gains exceeding 21% in the first half of 2026, marking its strongest performance for the first half of any year since 1991, according to market analysts including Alger fund managers. The rally reflects a reversal from years of underperformance relative to large-cap stocks, driven primarily by artificial intelligence infrastructure investment spillovers, valuation normalization, and improving fundamentals.

Within Russell 2000's top 50 performers year-to-date, 16 stocks are semiconductor and chip-related companies, including Aehr Test Systems and Amkor Technology, with some climbing over 400%. Alger managers noted the valuation gap between large and small caps has compressed significantly. Russell 2000 earnings growth expectations have been raised from 23% at year-start to 38% for full-year 2026, as profit expansion spreads from large technology leaders to mid-sized suppliers. Higher interest rates remain a potential headwind, as small firms carry greater floating-rate debt exposure; Bank of America estimates each 25 basis point rate increase could reduce Russell 2000 operating profits by approximately 2%.