
BlackRock's iShares Bitcoin Trust (IBIT) dominates the US spot Bitcoin ETF market with $47.95 billion in assets under management as of June 2026, holding about 61% market share. Fidelity's Wise Origin Bitcoin Fund (FBTC), launched alongside IBIT in January 2024, manages $11.3 billion but trails significantly. Both ETFs offer similar Bitcoin exposure and fees, but BlackRock's brand strength and distribution give it a clear edge. Despite recent outflows amid Bitcoin's price drop in early 2026, IBIT is expected to maintain its lead unless Fidelity introduces new competitive advantages or sees accelerated inflows.