Bitcoin ETFs turn 2026 flows positive after $2.4 billion week

US spot bitcoin exchange-traded funds took in $2.4 billion in the week to September 25, their best week since October 2025. That pushed their 2026 net flows above zero, two months after the funds sat $5.8 billion in the red.

The figures come from data provider SoSoValue, reported by The Block on 26 September. By Friday the funds were about $934.1 million positive for the year, after their year-to-date flows crossed back into the green on Tuesday. The last time a week ran hotter was October 2025, when the funds took in $2.7 billion.

Where the money went

BlackRock's iShares Bitcoin Trust (IBIT) pulled in about $1.2 billion over the week, its second-biggest week since October 2025, behind the $1.3 billion it drew in the week to 21 August. Fidelity's Wise Origin Bitcoin Fund (FBTC) added $701.7 million. Across all the US funds, cumulative inflows since the January 2024 launch now stand at $57.6 billion, with net assets of $108.4 billion as of Friday.

The buying was front-loaded. Monday brought $999.0 million, the largest single day since 6 October 2025. Then it faded. Tuesday saw $714.7 million, Wednesday $347.0 million, Thursday $190.6 million and Friday $134.5 million.

What drove the money back in

Analysts tied the return of demand to an unusual place: US government bond policy. On 19 August the Treasury Department said it would raise the maximum size of its liquidity-support buybacks of longer-dated Treasury securities. Since that announcement, about $5.3 billion has flowed into the bitcoin funds, according to crypto.news.

Eric Balchunas, an ETF analyst at Bloomberg, called the reversal a "$4.6 billion tsunami of cash" and linked it to the buyback plan. Nate Geraci, president of NovaDius Wealth Management, said Monday's inflow ranked as the ninth-largest single day since the funds launched. Neither the size of the buyback program nor the flows prove the buyers plan to stay.

Why the cooling matters

Weekly totals can hide the shape of the demand. This one shrank every day after Monday. Flows can reverse fast. The run stretched to seven straight trading days, worth about $3 billion in all, before the pace eased. A single policy shift moving billions into a fairly new asset class is exactly the kind of money that can leave as quickly as it came. Spot ether funds drew $689.9 million over the same week, so the appetite was not limited to bitcoin.

Bitcoin itself has been quiet through the run. It traded near $84,783 at 20:16 UTC on 27 September 2026, up about 1 percent on the day, according to CoinGecko. The price has held near $84,000 for weeks, even as regulators widened the path for new crypto ETPs.

What to watch

Watch whether the daily inflows steady or keep shrinking in the week ahead. If Monday's burst was a one-off tied to the Treasury move, flows could flatten or turn negative again. A steady stream across a full week would say more about lasting demand than any single record day. The funds have erased this year's deficit. Holding onto it is the harder part.