IBIT, FBTC or ARKB: Which Spot Bitcoin ETF Is the Best Pick?

IBIT, FBTC and ARKB are three spot bitcoin ETFs holding the same thing - real bitcoin, stored by a custodian - so none of them will outperform the others on what bitcoin does. The best pick among them is decided by three dull numbers: the fee, the size of the fund, and who holds the coins. Here is how the three line up.

How do the three compare?

ARKB, run by ARK and 21Shares, charges 0.21% a year and held around $2.9bn in October 2026. IBIT, BlackRock's fund, and FBTC, Fidelity's, both charge 0.25%; IBIT held about $69bn and FBTC about $16bn. So ARKB is marginally the cheapest and much the smallest, IBIT is the most expensive of the three by a hair and many times the largest, and FBTC sits in between while storing its bitcoin in-house rather than at Coinbase, where IBIT's and ARKB's coins sit.

Is a 0.04% fee gap worth chasing?

Do the arithmetic before you decide. On a $10,000 holding, 0.25% is $25 a year and 0.21% is $21. That four-dollar difference is roughly one coffee, and it is smaller than the trading spread you might pay getting in and out of a thinner fund twice. A fee gap matters when it is measured in whole percentage points, as it is with Grayscale's original 1.50% trust - not when it is measured in hundredths.

What matters more than the ticker?

Two things. First, where you hold it: a fund bought commission-free inside the brokerage you already use beats a marginally cheaper one that costs you a trading fee each time. Second, concentration - most of these funds keep their bitcoin with the same custodian, and spreading across three of them does not spread that risk as much as the three logos suggest.

Before buying any of them, open the issuer's own fund page and confirm the fee and assets for yourself, because both move. For the two-way version, read IBIT vs FBTC; for the whole field, see every bitcoin ETF compared.