Bitcoin and Ether ETFs Pull In $2.61 Billion in Strongest Week Since October

U.S.-listed spot Bitcoin and Ether exchange-traded funds attracted a combined $2.61 billion across five trading sessions, marking their strongest weekly performance since October 2025. The positive flow reversed the previous week's combined $391.96 million withdrawal by approximately $3.01 billion, with both asset categories recording positive daily inflows throughout every session of the week.

Bitcoin ETFs Capture the Majority of Inflows

Spot Bitcoin ETFs received $1.92 billion, accounting for 73% of the combined weekly inflows. Data from SoSoValue showed that U.S. spot Bitcoin ETFs added $307 million on Aug. 21 alone, extending their positive daily streak to five consecutive sessions. BlackRock's iShares Bitcoin Trust (IBIT) led the final session with $239 million, while Fidelity’s Wise Origin Bitcoin Fund (FBTC) followed with $30.19 million. By the end of the week, IBIT’s cumulative net inflows reached $62.43 billion, and all U.S. spot Bitcoin ETFs held $96.07 billion in net assets.

Ether Funds Add Nearly $700 Million

Spot Ether ETFs pulled in $697.47 million over the five sessions, posting gains every single day. The category added $185 million on Aug. 21, led by BlackRock’s iShares Ethereum Trust ETF (ETHA) with $151 million and Grayscale’s Ethereum Mini Trust ETF with $11.51 million. ETHA's total net inflows reached $12.17 billion since its launch, while the entire category finished the week holding $14.30 billion in net assets.

BlackRock Dominates Daily Allocation

BlackRock captured the majority of institutional demand during the final session on Aug. 21, pulling in a combined $390 million across both its IBIT and ETHA funds. This accounted for roughly 79% of the day's $492 million aggregate Bitcoin and Ether ETF inflows. Combined, all U.S. spot Bitcoin and Ether ETFs held approximately $110.36 billion in net assets by the close of the week.