Bitcoin ETFs Soar with $3.8B Inflow Streak Amid September Rally

US spot Bitcoin ETFs have attracted $3.8 billion in the past three weeks, their strongest such stretch of 2026, according to SoSoValue data.

The category drew $986.9 million alone in the week ending September 5, bringing its total net assets to over $101.3 billion by that date. Cumulative inflows since launch have reached $55.6 billion.

This three-week run follows a difficult start to the year for Bitcoin ETFs, which experienced heavy outflows and remain roughly $1 billion in the red year-to-date despite recent recovery. Net flows were more measured on September 5, totaling $174.6 million with BlackRock's iShares Bitcoin Trust leading the day at $117.4 million.