During the first full week of May 2026, U.S. spot bitcoin exchange-traded funds pulled in a net 31,500 BTC, according to daily creation and redemption data tracked by Farside Investors. Over that same stretch, bitcoin miners produced roughly 3,150 new coins. The ratio: ten to one. It was not an anomaly. Since late 2024, high-inflow weeks have repeatedly seen ETF purchases outstrip new mining supply by a wide margin, a dynamic rooted in two events that landed barely three months apart and fundamentally rewired bitcoin’s market structure.
A new buyer class meets shrinking supply
On January 10, 2024, the SEC authorized U.S. exchanges to list spot bitcoin ETFs for the first time. The approval opened the door for pension funds, registered investment advisers, and ordinary brokerage accounts to gain bitcoin exposure through the same platforms they use for stocks and bonds. Products launched fast: BlackRock’s iShares Bitcoin Trust (IBIT), Fidelity’s Wise Origin Bitcoin Fund (FBTC), ARK 21Shares Bitcoin ETF (ARKB), and roughly a dozen others began trading within days.
Because each ETF share must be backed by actual bitcoin held in custody, every dollar of net inflow translates into a real purchase on spot markets. By early 2025, cumulative net inflows across all U.S. spot bitcoin ETFs had surpassed $35 billion, according to Farside and Bloomberg Intelligence. IBIT alone crossed $20 billion in net inflows faster than any ETF in history. “It’s not even close to any prior launch,” Bloomberg ETF analyst Eric Balchunas wrote at the time. Through the rest of 2025 and into 2026, inflows continued to accumulate, pushing total assets under management across the category well beyond those early milestones.
Then came the halving. On April 19, 2024, Bitcoin’s protocol automatically cut the block reward from 6.25 BTC to 3.125 BTC, dropping daily new issuance from roughly 900 coins to about 450. Halvings occur every 210,000 blocks, approximately every four years, and are hard-coded into Bitcoin’s software. The timing was predictable. What nobody could have predicted was that a massive new channel of regulated demand would already be ramping up when the supply cut hit.
Quantifying the gap
At 450 BTC mined per day, weekly new supply totals about 3,150 coins. During strong inflow weeks in late 2024, throughout 2025, and into 2026, U.S. spot bitcoin ETFs collectively absorbed 4,000 to 7,000 BTC or more in net new purchases per week, based on fund flow data from Farside Investors cross-referenced with on-chain analytics from Glassnode. On peak days, the ratio of ETF buying to mined supply has exceeded 10-to-1.
That ratio is not constant. ETF flows swing with sentiment: risk-off weeks have produced net outflows, temporarily flipping funds from buyers to sellers. Early in the ETF era, Grayscale’s converted Bitcoin Trust (GBTC) generated significant outflows as legacy holders rotated into lower-fee competitors, partially offsetting the headline inflow numbers. But the trend since launch has been overwhelmingly positive. By mid-2026, U.S. spot bitcoin ETFs collectively hold well over 1.1 million BTC in custody, representing more than 5.5% of bitcoin’s total circulating supply of roughly 19.8 million coins, per on-chain tracking by Arkham Intelligence.
A note on methodology: no single official source publishes a real-time, consolidated daily purchase figure for all spot bitcoin ETFs. Fund sponsors disclose holdings periodically through SEC EDGAR filings, and analysts piece together daily estimates from creation and redemption data paired with on-chain wallet tracking. The ten-to-one ratio reflects high-inflow periods rather than a fixed, audited daily average. Even conservative readings of the data, however, show ETF demand routinely dwarfing new mining output.
What miners are doing about it
The halving did not just squeeze supply for ETF buyers. It also squeezed miner economics. With the block reward cut in half, miners earning 3.125 BTC per block need bitcoin’s price to be significantly higher just to cover the same electricity and hardware costs they faced before April 2024.
Publicly traded miners have responded in divergent ways. Marathon Digital (MARA) and CleanSpark (CLSK) expanded capacity and acquired smaller competitors. Several large miners adopted what the industry calls a “HODL treasury” approach, holding mined bitcoin on their balance sheets rather than selling immediately. That strategy further tightens available supply: when miners choose not to sell, the effective daily flow of new coins reaching the open market drops below the theoretical 450 BTC.
They are not the only corporate buyers compounding the squeeze. Strategy, the software company formerly known as MicroStrategy, has continued its aggressive bitcoin accumulation program, holding over 200,000 BTC on its balance sheet as of early 2026, according to its public filings. Between ETF inflows, miner hoarding, and corporate treasury buying, the share of newly mined bitcoin that actually reaches the open market has narrowed considerably.
Smaller or less efficient miners, meanwhile, face pressure to sell everything they produce or shut down entirely, concentrating hash power among larger, better-capitalized operators.
Why it matters for price
Bitcoin traded near $44,000 when the spot ETFs launched in January 2024. By the halving in April, it had already climbed past $60,000, driven in part by ETF-related buying. Through late 2024 and into 2025, prices pushed higher still, with bitcoin crossing the $100,000 mark for the first time, a level that would have seemed speculative just two years earlier.
Attributing all of that move to the ETF supply squeeze would be an oversimplification. Macro factors played significant roles: Federal Reserve rate expectations, dollar strength, and broader risk appetite all shifted during this period. So did momentum trading, options market dynamics, and renewed retail interest. But the structural math is hard to dismiss. When a new class of regulated buyer consistently absorbs many times more bitcoin than the network produces, the available float shrinks, and sellers gain pricing power.
The comparison to gold is instructive. When State Street launched the SPDR Gold Shares ETF (GLD) in November 2004, it created a similar dynamic: a new, accessible demand channel for an asset with constrained supply. Gold was trading around $440 an ounce at the time. Within seven years it had topped $1,800, roughly a fourfold increase. Bitcoin’s supply schedule is even more rigid than gold’s. Mining difficulty adjustments and the halving cycle are governed by code, not geology or economics, and the total supply is capped at 21 million coins.
What could break the squeeze
Several forces could ease or reverse the imbalance. A sustained period of ETF outflows, triggered by a broader market selloff or a shift in investor sentiment, would reduce demand. Regulatory changes, whether new SEC guidance, tax policy shifts, or restrictions in other jurisdictions, could alter the flow of capital into these products. Large holders (often called whales) sitting on significant bitcoin reserves could move coins to exchanges, adding supply without any change in mining output.
There is also the question of competing products. Spot bitcoin ETFs now trade in Canada, Europe, Hong Kong, and Australia. If global demand fragments across more vehicles and jurisdictions, the concentration of buying pressure through U.S.-listed funds could moderate. Conversely, if other major markets, notably the U.K. and Japan, approve similar products, the total pool of ETF-driven demand could grow further.
A structural shift, not a temporary spike
The setup that produced this supply squeeze is not going away. The next halving, expected around April 2028, will cut the block reward again, to 1.5625 BTC. Daily new issuance will drop to roughly 225 coins. If ETF demand holds anywhere near its current trajectory, the ratio of institutional buying to new supply will only widen.
For now, the dynamic is straightforward: a programmatically fixed and recently halved supply of new bitcoin is meeting a fast-growing, institutionally backed demand channel that did not exist before January 2024. The precise daily ratio will fluctuate with market conditions and sentiment. But the structural imbalance is not a projection or a theory. It is visible in fund filings, on-chain data, and the price chart itself.
