Blackrock’s IBIT Nears 600,000 BTC as ETF Reserve Growth Accelerates

U.S. spot bitcoin exchange-traded funds amassed $3.06 billion in inflows last week, according to newly published figures. Meanwhile, Blackrock’s IBIT fund edges closer to the 600,000 $BTC threshold, requiring just 11,314 $BTC to eclipse this significant benchmark.

Three Bitcoin ETFs Now Hold Almost 1 Million $BTC Combined

Data compiled by sosovalue.com reveals that since Jan. 11, 2024, U.S. spot bitcoin ETFs have attracted $38.43 billion in inflows, with last week’s addition contributing $3.06 billion to that total. On Friday alone, Blackrock’s IBIT garnered $240 million, further bolstering its reserves. As of April 27, 2025, figures drawn from Blackrock’s own portal show IBIT holding 588,686.91 $BTC, translating to $55.3 billion based on Sunday’s bitcoin valuation.

With approximately 19.85 million $BTC currently in circulation, IBIT commands 2.97% of the outstanding supply. Fidelity’s FBTC maintains a holding of 199,684.83 $BTC, valued at $18.76 billion, while Grayscale’s GBTC stockpiles 191,190.971 $BTC, equating to roughly $17.9 billion as of Sunday, April 27. These three funds are the only ETFs surpassing the 100,000 $BTC mark, collectively overseeing 979,562.711 $BTC valued at $92 billion. Together, IBIT, FBTC, and GBTC collectively steward 4.93% of bitcoin’s circulating quantity.

Beyond these, just three other funds possess more than 35,000 $BTC apiece, including Ark Invest’s ARKB with 52,604 $BTC. Grayscale’s Bitcoin Mini Trust holds 42,079.29 $BTC, and Bitwise’s BITB maintains a reserve of 39,020.06 $BTC as of April 27. Combined, the trio accounts for 133,703.35 $BTC, estimated at $12.5 billion, representing a comparatively smaller 0.67% of the current 19.85 million supply. An additional six funds—HODL, BRRR, BTCO, EZBC, BTCW, and DEFI—together hold 32,646.156 $BTC, valued just north of $3 billion based on prevailing exchange rates.

Altogether, U.S. spot bitcoin ETFs hold a combined total of 1,145,912.217 $BTC, amounting to $107.70 billion as of April 27. This trove corresponds to 5.77% of the existing 19.85 million $BTC in circulation. When factoring in international ETFs alongside holdings by public and private companies, the volume of bitcoin committed to long-term storage grows substantially larger.