ARKB vs BITB: A Bitcoin ETF Comparison

ARKB and BITB are two spot bitcoin ETFs of almost identical size, and they hold the same thing: real bitcoin, kept by a custodian on the fund's behalf. ARKB is run by ARK Invest with 21Shares and charges 0.21% a year. BITB is Bitwise's fund and charges 0.20%. That one hundredth of a percent is the entire difference in price, which makes this comparison less dramatic than the ticker-versus-ticker framing suggests.

How big is each fund?

In mid-October 2026 BITB held about $3.0bn and ARKB about $2.9bn - near twins, and both far smaller than BlackRock's IBIT at roughly $66bn. Size affects the spread you pay when buying and selling rather than how safe the fund is, and at $3bn each both are liquid enough that an ordinary purchase will not move the price against you.

What is the fee difference really worth?

Do the arithmetic instead of trusting the ranking. On $10,000 held for a year, 0.21% costs $21 and 0.20% costs $20. One dollar. A single trading commission at your broker, or a slightly wider spread on the morning you happen to buy, will swallow that several times over. Fee gaps matter when they are whole percentage points - as with Grayscale's original GBTC trust at 1.50% - not hundredths.

Is there anything else between them?

Two things, both small. Both funds store their bitcoin with Coinbase, so holding one instead of the other changes nothing about custody risk. And Bitwise publishes the wallet addresses that hold BITB's bitcoin, so anyone can look up the coins on a block explorer the way you would check a receipt; ARK does not. If being able to verify holdings yourself appeals to you, that is the real tiebreaker here.

Whichever you pick, check the fee on the issuer's own page first - both have moved before - and buy inside a brokerage that charges you nothing for the trade. For the bigger two funds, read IBIT vs FBTC; for the whole table, see the best spot bitcoin ETFs compared.