The demand has spread beyond bitcoin: spot Ether ETFs took in about $270 million in the same session, their best day since October 2025, led by BlackRock's ETHA. Monday also extended the bitcoin funds' inflow streak to three sessions and lifted total net assets above $110 billion. Sentiment support is building, because holders sitting on gains are generally less inclined to sell into strength than holders waiting to get back to breakeven. The combination of heavy short liquidations and fresh fund buying also means positioning has been cleared out, which leaves the next leg more dependent on genuine demand than on forced covering.---Bitcoin ETFs have wiped out this year's outflows, but part of the rally was forced buying, so the test is whether the money keeps coming once the shorts are gone.Summary:Galaxy's Alex Thorn says US spot bitcoin ETF flows for 2026 have turned positive for the first time since April, after a session of roughly $1 billion in net inflows.SoSoValue data put Monday, September 21, at $998.95 million: the biggest day of 2026, led by IBIT ($381.4m), ARKB ($289.1m) and FBTC ($238.8m). Farside has not yet confirmed the figures.Bloomberg puts year-to-date flows at about +$320 million, with roughly $4.6 billion added since August 19, when the US Treasury flagged increased buybacks of long-dated bonds.Bitcoin is up about 35% since August 19 and touched $87,395 this week, its highest level since January.Nearly $919 million in crypto short positions were liquidated during the surge.Estimates of the average ETF cost basis sit near $81,700 to $82,000, putting the typical holder back in profit for the first time since January.US spot bitcoin ETFs have returned to net inflows for 2026, with year-to-date flows turning positive for the first time since April, according to Alex Thorn, head of research at Galaxy. Thorn said on X that a session of roughly $1 billion in net inflows had pushed the funds over the line.SoSoValue data put that session on Monday, September 21, with net inflows of $998.95 million. That was the largest single day of 2026 and the strongest since October 2025. BlackRock's IBIT led with $381.4 million, followed by ARK 21Shares' ARKB at $289.1 million and Fidelity's FBTC at $238.8 million. Farside Investors had not yet updated its figures at the time of writing, and coverage has not agreed on which session the inflow landed in, so the daily numbers should be treated as provisional until the data is confirmed.Bloomberg's tally shows a similar picture, putting the funds about $320 million in the black for the year. Roughly $4.6 billion has flowed in since August 19, when the US Treasury announced plans to step up buybacks of long-dated bonds. Over the same period bitcoin has gained about 35%, reaching $87,395 this week, its highest since January.This time, flows and price are moving in the same direction, which is not always the case. Earlier this year, steady redemptions coincided with a sagging price. Readers should still be careful about treating the inflows as proof of institutional conviction. Nearly $919 million of crypto short positions were liquidated during the latest surge, according to data cited by Investor's Business Daily. That means part of the price move reflected forced buying by traders who had bet on further declines.The rally has also changed the position of ETF holders. Bloomberg analyst James Seyffart estimates the average cost basis at about $81,722 per bitcoin, while Pepperstone's Chris Weston puts it near $82,000. That leaves the typical holder back in profit for the first time since January. Weston said he does not see the return to break-even as an obvious trigger for profit-taking.What to watch next is whether inflows continue once Farside confirms this week's sessions. A run of steady inflows with price holding above the $82,000 cost-basis area would strengthen the case that demand through these products is rebuilding. A slide back below that zone would put the average holder under water again and test how committed the new money is. For now, the practical read is to watch the flow trend and the price response together before treating one strong day as a turning point. This article was written by Eamonn Sheridan at investinglive.com.