US spot Bitcoin ETFs see nearly $1 billion in single-day inflows

US spot Bitcoin ETFs recorded $998.96 million in net inflows on September 21, marking the largest single-session total of 2026. BlackRock's IBIT led with $381.4 million, followed by ARK 21Shares' ARKB with $289.1 million and Fidelity's FBTC with $238.8 million. While this surge highlights significant institutional demand, it remains to be seen if this pace will be sustained in upcoming sessions.