Asset manager BlackRock significantly increased its exposure to Bitcoin and Ethereum, scooping up more than $1.8 billion worth of the assets over a five-day trading period ending August 21. The firm captured the largest share of inflows into U.S. spot cryptocurrency exchange-traded funds during one of the strongest weeks for the sector.
During the five-day span, BlackRock's spot Bitcoin and Ethereum ETFs recorded a combined $1.87 billion in net inflows. The iShares Bitcoin Trust (IBIT) attracted approximately $1.33 billion, while the iShares Ethereum Trust (ETHA) added $536.8 million. These combined figures positioned BlackRock as a key driver of the market rally.
Breakdown of Weekly Inflows
For IBIT, daily inflows were recorded as $160.2 million on August 17, $143.6 million on August 18, $284.7 million on August 19, $503 million on August 20, and $239.3 million on August 21. The largest single-day inflow occurred on August 20, aligning with a broader U.S. spot Bitcoin ETF collection of $606.3 million, which marked the highest daily total since May.
Ethereum products experienced similar institutional demand. BlackRock's ETHA absorbed $25.9 million on August 17, $64.7 million on August 18, $122.1 million on August 19, $173.3 million on August 20, and $150.8 million on August 21, culminating in a weekly total of $536.8 million.
Broader Market Impact
Across the wider U.S. spot crypto ETF market, Bitcoin funds attracted approximately $1.9 billion in net inflows, while Ethereum funds added nearly $700 million. Combined inflows reached about $2.6 billion, representing the strongest week for both categories since October 2025 and the largest weekly inflows of 2026. Trading volume across the funds tripled to roughly $29 billion, with BlackRock accounting for nearly 70% of Bitcoin ETF inflows and over 75% of Ethereum ETF inflows.
The surge in demand followed a rebound that saw Bitcoin climb above $77,000. Catalysts included the U.S. Treasury expanding long-dated bond buybacks, which weakened the dollar and increased alternative asset demand, alongside improved sentiment surrounding proposed U.S. crypto regulation such as the CLARITY Act and a market rally that triggered short covering.
