BlackRock’s iShares Bitcoin Trust ETF has established a commanding lead in the spot Bitcoin ETF market. As of June 26, 2025, IBIT reported approximately $44.87 billion in assets under management, holding 742,870 Bitcoin.
Fidelity’s Wise Origin Bitcoin Fund, its nearest competitor, manages between $10.4 billion and $13.5 billion in assets. Both products launched in January 2024 after the SEC approved spot Bitcoin ETFs, a decision that transformed institutional access to cryptocurrency markets.
IBIT reached $10 billion in assets faster than any prior ETF, signaling immediate institutional demand. Its scale creates a self-reinforcing liquidity advantage. Deeper trading volumes lead to tighter bid-ask spreads, lowering real-world costs for investors executing large orders. Once a fund becomes the liquidity leader, it tends to keep that position as execution quality drives further migration.
Both funds charge an identical expense ratio of 0.25%, removing cost as a competitive factor. The custody arrangements differ. Coinbase Custody handles Bitcoin for IBIT, while Fidelity Digital Assets manages custody for FBTC.
IBIT’s 742,870 Bitcoin represents a significant concentration of supply held in a single regulated vehicle. For active traders, the fund’s liquidity advantage has practical consequences, as tighter spreads on a volatile asset can meaningfully affect long-term returns.