BlackRock’s Bitcoin ETFs Become Firm’s Biggest Revenue Driver

BlackRock’s bitcoin exchange-traded funds have become the company’s strongest revenue engine, surpassing more than 1,400 ETFs in its global lineup, according to Cristiano Castro, director of business development at BlackRock Brazil.

Speaking at the Blockchain Conference in São Paulo, Castro called the rise of the firm’s bitcoin products “a big surprise” and confirmed that allocations across BlackRock’s BTC-linked ETFs — including the U.S.-listed IBIT and Brazil’s IBIT39 — have approached $100 billion.

“When we launched, we were optimistic, but we didn’t expect this scale.”

The growth has been led by the iShares Bitcoin Trust (IBIT), the U.S. spot bitcoin ETF introduced in January 2024. IBIT became the fastest ETF in history to reach $70 billion in assets, achieving the milestone in just 341 days. By October 2025, the fund was generating an estimated $245 million in annual fees.

SoSoValue data shows IBIT currently holds around $70.7 billion in net assets and has accumulated more than $52 billion in net inflows in its first year. The ETF now controls over 3% of bitcoin’s circulating supply.

Castro noted that the ETF’s performance has been supported by BlackRock’s global distribution network and increased institutional demand following U.S. approval of spot bitcoin ETFs. He also commented on recent outflows from BTC funds, saying such fluctuations are normal during price pullbacks.

“ETFs are a very liquid and powerful tool. They’re meant for people to manage flows.”

BlackRock itself continues to deepen its exposure: the firm’s Strategic Income Opportunities Portfolio recently increased its position in IBIT by 14%, signaling internal confidence in long-term growth.

CoinDesk contacted BlackRock for additional comment but did not receive a response at the time of publication.