American spot exchange-traded funds for Bitcoin and Ethereum demonstrated impressive momentum, attracting a combined $2.6 billion during the trading week of August 17-21. This is the strongest result since October 2025, signaling the return of institutional risk appetite after a prolonged correction phase.
Bitcoin ETFs bore the brunt of the inflows, accumulating $1.92 billion. Notably, inflows were recorded for five consecutive trading sessions, with the peak occurring on August 20, when funds received $606 million in a single day. Ethereum-based products also showed solid growth: inflows totaled $697.18 million, more than offsetting the $391.96 million outflow recorded the previous week.
Record Activity and a Shift in Trend
Alongside capital inflows, trading volumes surged. During the reporting period, Bitcoin ETFs facilitated $22.15 billion in trades — nearly three times more than over the previous seven days. This week effectively broke a prolonged streak of outflows: the cumulative net inflow into Bitcoin funds, which peaked at $62.77 billion in October 2025, had previously fallen to $53.71 billion, but the trend has now reversed.
Ethereum funds also posted their best day since October: on August 20, they attracted $220.77 million. Nevertheless, assets under management remain 53% below the record levels of August 2025, indicating significant room for recovery.
Asset Growth vs. Capital Inflows: An Important Nuance
However, inflows alone do not explain the full picture. The total value of assets in both ETF categories rose by approximately $23 billion, while investors contributed only $2.6 billion. This means the primary driver of growth was the revaluation of the coins themselves: Bitcoin funds appreciated by 22.9% excluding new contributions, while Ethereum funds rose by 29.2%. The lion's share of this rally occurred over three trading days from August 19-21. At the time of analysis, BTC was trading near $76,230, while ETH was around $2,406.
Altcoin ETFs: A New Wave of Interest
Demand also extended to altcoins. The week's leader was the XRP ETF with inflows of $39.78 million and record trading volume of $271.74 million. Solana funds took second place with $28.34 million, marking their eighth consecutive week of positive momentum. Chainlink products attracted $13.35 million — the second-best result since their launch in December 2025.
Hyperliquid (HYPE) ETFs added $3.89 million, with their total assets reaching an all-time high of $360.39 million. Dogecoin funds round out the list with a symbolic $654,416.
My take: The current momentum is not merely a bounce but a shift in market regime. Asset value growth outpacing capital inflows suggests that investors are holding positions in anticipation of further rallies. However, for a sustained bull trend, consolidation of inflows at current levels is necessary; otherwise, we risk seeing another correction at the first sign of profit-taking.