US spot Bitcoin and Ether exchange-traded funds recorded their strongest day since October 2025 on Monday, September 21, taking in net inflows of $998.95 million and $269.98 million, respectively, according to SoSoValue data.

The daily tallies marked the largest single-day hauls for Bitcoin ETFs since October 6, 2025, and for Ether ETFs since October 7, 2025, underscoring a market-wide resurgence and a return of institutional funds to crypto products that have pushed Bitcoin as high as $87,000 after a difficult year. Because spot ETFs hold the underlying coins and trade through ordinary brokerage accounts, their daily flows are widely tracked as a gauge of institutional appetite for regulated crypto exposure.

Spot Solana and XRP ETFs, the third- and fourth-largest crypto ETFs by assets under management, logged $26.1 million and zero net flows, respectively, on the day — a far quieter showing than the two flagship products.

BlackRock's Bitcoin ETF led daily inflows

BlackRock's iShares Bitcoin Trust (IBIT) secured the largest share of the nearly $1 billion drawn by Bitcoin ETFs on September 21, with $381.4 million. The ARK 21Shares Bitcoin ETF (ARKB) followed with $289.1 million, while Fidelity's Wise Origin Bitcoin Fund (FBTC) rounded out the top three at $238.8 million, per SoSoValue.

Grayscale, Bitwise and Morgan Stanley also posted positive flows across the funds they operate.

Monday's figure set a new 2026 record for daily Bitcoin ETF inflows, pushing the previous $844 million high, set on January 14, into second place. It remains short of the $1.2 billion recorded on October 6, 2025.

On the year, US spot Bitcoin ETFs have shed about $464 million in net terms, with Cryptopolitan reporting that the products endured roughly $4.5 billion in June redemptions. The tide has turned positive since August, however, after a $3.52 billion net inflow month. Since the funds began trading on January 11, 2024, they have drawn about $55.6 billion in cumulative net inflows — and at Monday's pace, only a small number of similar sessions would be needed to swing the year back into net positive territory.

Prices cleared a level that had capped the market

Bitcoin traded near $86,000 early Tuesday after touching roughly $87,300 on Monday, its highest mark since January 2026. Ether rose nearly 11% over the past week, and analysts pointed to a short squeeze layered on top of the fresh buying — a dynamic in which climbing prices force bearish traders to buy back to close positions, accelerating the move. CoinGlass recorded $1.06 billion in crypto liquidations over 24 hours, of which about $844 million came from short positions.

CryptoQuant's Julio Moreno said Bitcoin had pushed above its 365-day moving average, a long-term trend line often used to judge whether an asset has shifted into a sustained uptrend, which he described as the last confirmation he wanted to see for a new bull market.

Analysts have tied the rebound to a friendlier macroeconomic backdrop: softer oil prices, easing Treasury yields and a scheduled meeting between US President Donald Trump and Chinese President Xi Jinping.

Dominick John, an analyst at Zeus Research, said the durability of the move now hinges on flows. “Traders are watching whether BTC holds above $85,000 and ETH above $2,700, with sustained spot ETF inflows signaling underlying demand,” he told The Block. With the 2026 inflow record now reset, those price levels and the daily flow data form the near-term checklist for judging whether Monday's haul marks a turning point.