Bitcoin ETF Streak Hits $3.1B as Ether Funds Reverse

US spot Bitcoin ETFs extended their net inflow streak to nine trading days, taking in about $3.1 billion from 17 Sep through 29 Sep 2026, according to Farside’s Bitcoin ETF data. Ether ETFs moved the other way, recording $2.8 million of net outflows on 29 Sep and ending a seven-day inflow run.

The Bitcoin streak was not evenly distributed across the funds. On 21 Sep, the strongest session of the run, US spot Bitcoin ETFs received $999.0 million. BlackRock’s IBIT took in $381.4 million, while ARKB received $289.1 million, according to Farside.

The nine-day run began on 17 Sep, when the funds recorded $159.5 million in net inflows. The table shows positive net flow on every session through 29 Sep, taking the period total to roughly $3.1 billion. The next session, 30 Sep, broke the pattern with $148.7 million in net outflows, led by a $125.6 million outflow from Fidelity’s FBTC.

That reversal matters for the broader institutional picture. Bitcoin ETFs have accumulated $57.564 billion in net inflows since launch, according to Farside. BlackRock’s IBIT has recorded $65.378 billion in gross inflows, while Grayscale’s GBTC remains a $27.865 billion net drag. The aggregate total shows the scale of the market, but the product-level figures also show why a single session matters: demand is concentrated, and flows can reverse quickly.

Ether’s Inflow Run Breaks

Ether ETFs recorded $2.8 million in net outflows on 29 Sep, ending seven consecutive sessions with inflows. BlackRock’s ETHA lost $8.9 million and Fidelity’s FETH lost $6.7 million, while Grayscale Mini ETH received $12.8 million, according to Farside’s Ether ETF table.

The reversal widened on 30 Sep. Ether ETFs lost $59.6 million, with FETH down $26.6 million, Grayscale Mini ETH down $25.5 million and ETHE down $7.5 million. A single day does not erase the preceding inflow period, but it removes the clean momentum signal that had been present through 29 Sep.

Farside lists cumulative net inflows to Ether ETFs at $13.924 billion since launch. ETHA accounts for $13.289 billion, while ETHE remains negative at $5.420 billion. Ether ETF flows have also been uneven during September: the funds saw $224.1 million of outflows on 16 Sep and $142.0 million on 15 Sep.

What The Divergence Means

The data points to a different allocation pattern between the two assets. Bitcoin ETFs recorded positive net flow for nine sessions and then lost $148.7 million on 30 Sep. Ether ETFs moved from seven positive sessions to $2.8 million of outflows, then to $59.6 million the following day.

For institutional allocation, the immediate test is whether Bitcoin can return to positive flow after the 30 Sep outflow, and whether Ether can recover its seven-session pattern. A renewed Bitcoin outflow would weaken the claim that the streak represented a broader, persistent shift. A continued Ether reversal would make the divergence look less like a one-day pause and more like a change in fund positioning.

The flows do not establish a price target or tell traders what to do next. They do show where the buying was concentrated, how quickly it can stop, and which sessions would confirm or invalidate the current reading.