Bitcoin News
BlackRock’s IBIT commands the Bitcoin ETF market
IBIT captures massive inflows during recovery
BlackRock’s iShares Bitcoin Trust (IBIT) captured $686.8 million in net inflows between September 2 and September 4, 2026. This three-day period saw total US spot Bitcoin ETF inflows reach $1.01 billion. IBIT alone accounted for roughly two-thirds of those total inflows. IBIT’s dominance remains high as it controls about 75% of the entire spot Bitcoin ETF market. On August 24, IBIT recorded $208.9 million in net inflows, which accounted for approximately 61.9% of the $337.6 million total net inflows reported across all tracked US spot Bitcoin ETFs. This recovery followed a difficult period in August when the category saw total net outflows of $56.2 million on August 14. IBIT alone lost 874.61 BTC on that same day. On August 12, IBIT lost 224.94 BTC. During the six-day run from August 17 to August 24, IBIT pulled in a sequence of daily inflows including $160.2 million on August 17, $143.6 million on August 18, $284.7 million on August 19, $503.0 million on August 20, $239.3 million on August 21, and $208.9 million on August 24. On September 8, the market saw a reversal when US spot Bitcoin ETFs recorded $46.6 million in net outflows. IBIT still pulled in $10.7 million during that specific outflow session.
Comparing liquidity and custody models
IBIT maintains a significant lead over Fidelity’s FBTC in both liquidity and total assets. IBIT holds 785,023.8 BTC as of September 18, 2026, while FBTC holds 185,610 BTC. The $63.82 billion in assets under management held by IBIT dwarfs the $14.34 billion held by FBTC. You should know that higher trading volume in IBIT often creates tighter bid-ask spreads for active traders.
| Metric | IBIT (BlackRock) | FBTC (Fidelity) |
|---|---|---|
| AUM (as of 09/18/2026) | $63.82 billion | $14.34 billion |
| Expense Ratio | 0.25% | 0.25% |
| Custodian | Coinbase | Fidelity Digital Assets |
| BTC per Share | 0.000566 | 0.000870 |
Fidelity offers a distinct operational structure because it self-custodies Bitcoin through Fidelity Digital Assets. Most other major funds, including IBIT, rely on Coinbase for custody. The 1.33 billion shares outstanding in IBIT provide deep liquidity for large positions. Both funds launched on January 11, 2024, and they share an identical 0.25% expense ratio. IBIT’s share price was $44.735 on August 24. FBTC’s price sat at $70.66 on September 18. Does the market eventually favor self-custody models over third-party providers?
Fee drag and the competitive landscape
The 0.25% annual expense ratio for IBIT is a constant drag on Bitcoin holdings. The fund covers its operating costs through the daily sale of small amounts of Bitcoin, which reduces the Bitcoin-per-share ratio over time. After one year, each IBIT share represents approximately 0.25% less Bitcoin than at the time of purchase. For a 1,000-share position totaling 0.5662 BTC, the five-year fee drag reduces exposure to roughly 0.5592 BTC. At a Bitcoin price of $100,000, this five-year drag costs about $704. This reduction in Bitcoin per share happens because the fund must sell assets to pay for its management.
Lower-cost competitors challenge the dominance of the two largest funds. Morgan Stanley’s MSBT charges a 0.14% fee, while Grayscale’s Bitcoin Mini Trust charges 0.15%. Bitwise’s BITB and VanEck’s HODL both charge 0.20%, and ARK 21Shares’ ARKB charges 0.21%. Even though these differences seem small, they compound over long periods. Grayscale’s original GBTC carries a much higher 1.50% fee. Bitwise’s BITB holds 41,500 BTC, while ARK’s ARKB holds 40,140 BTC. Fidelity’s FBTC holds $14.34 billion in assets. Grayscale’s Bitcoin Mini Trust holds 34,760 BTC.
