The Bitcoin ETFs that matter most by AUM in 2026 are BlackRock IBIT, Fidelity FBTC, and Grayscale GBTC in the first tier, followed by ARK 21Shares ARKB, Bitwise BITB, VanEck HODL, WisdomTree BTCW, Invesco Galaxy BTCO, Franklin EZBC, and Valkyrie BRRR. IBIT alone accounts for more than half the category’s AUM, a concentration pattern that became structurally entrenched within twelve months of the January 2024 spot ETF approvals.