BlackRock is quickly establishing itself as the leading institutional custodian for Bitcoin and Ether, reshaping the market’s power balance in 2025. Its iShares exchange-traded funds (ETFs) have accelerated asset accumulation, putting the investment giant ahead of traditional crypto exchanges in both Bitcoin and Ether holdings.
Ethereum Custody Shift
BlackRock’s iShares Ethereum ETF (ETHA) now holds around 3.6 million ETH, narrowing the gap with Coinbase, which manages 3.8 million ETH. The fund added 1.2 million ETH in less than two months, a pace that could see it overtake Coinbase by the end of the year. Binance remains the largest Ether custodian with 4.7 million ETH, but its lead has shrunk considerably.
The shift marks a major change in custody dynamics. Coinbase, once the dominant Ether custodian with more than 8 million ETH in 2019, has seen its reserves decline by more than half over six years. Binance’s growth has slowed after years of expansion, while institutional inflows into BlackRock’s ETFs signal rising confidence in regulated products over exchange-based storage.
Bitcoin Holdings Hit Record Levels
The trend extends beyond Ether. BlackRock’s iShares Bitcoin Trust (IBIT) now holds roughly 745,357 BTC, surpassing Coinbase’s 706,150 BTC and Binance’s 584,557 BTC. This makes BlackRock the single largest institutional custodian of both leading cryptocurrencies, cementing its role in shaping the market’s structure.
Exchange Inflows Decline
On-chain data also reveals a notable slowdown in crypto exchange deposits. According to CryptoQuant, Bitcoin’s 30-day average inflows have fallen to their lowest level since May 2023, even as BTC trades near $111,000. Ether inflows show a similar pattern, dropping to levels last seen when ETH was priced at $1,700—despite the asset now trading closer to $4,600.
Lower inflows suggest reduced selling pressure, as both retail and institutional investors appear more inclined to hold rather than liquidate assets at current prices.
ETF Demand Outpaces Exchange Activity
Investor demand has clearly shifted toward ETFs. Ether funds have attracted over $1.5 billion in net inflows since last week, including $450 million in a single day. Bitcoin ETFs, after experiencing $1.17 billion in outflows last week, have rebounded with nearly $310 million in inflows over the past two days.
This divergence between declining exchange activity and growing ETF demand reflects a tightening supply backdrop, which many analysts believe could sustain bullish momentum in both Bitcoin and Ether heading into year-end.
