Spot Bitcoin ETF Data Comparison
The table compares IBIT, FBTC, ARKB, and BITB by issuer, exchange, expense ratio, custody, AUM, Bitcoin held, liquidity, and practical investor fit.
| ETF | Issuer / exchange | Expense ratio | Custodian | AUM / BTC held | Liquidity read | Best use |
|---|---|---|---|---|---|---|
| IBIT | BlackRock iShares / Nasdaq | 0.25% | Coinbase Custody | $62.65B AUM; about 817,138 BTC held as of May 15, 2026 | Largest product in this group; deepest listed options market | Core Bitcoin ETF position, active rebalancing, options overlay |
| FBTC | Fidelity / Cboe BZX | 0.25% | Fidelity Digital Asset Services | Second-tier spot BTC ETF scale; materially smaller than IBIT but still institutionally sized | Strong daily liquidity, but options depth is not IBIT-level | Custody diversification away from Coinbase |
| ARKB | ARK 21Shares / Cboe BZX | 0.21% | Coinbase Custody | Mid-sized spot BTC ETF; smaller than IBIT and FBTC | Tradable for normal orders; less useful for deep options strategies | Lower fee plus ARK/21Shares brand exposure |
| BITB | Bitwise / NYSE Arca | 0.20% | Coinbase Custody | Mid-sized spot BTC ETF; smaller than IBIT and FBTC | Normal ETF liquidity, but secondary options depth | Lowest fee among the four and crypto-native issuer positioning |
Flow, Options, And Trading-Use Comparison
This table focuses on the trading side of the comparison: where marginal flows may go, how deep the options market is, and what can change the ranking.
| ETF | Flow position | Options depth | Bid-ask spread sensitivity | What can change the ranking |
|---|---|---|---|---|
| IBIT | Most likely to capture the largest marginal inflows when institutions add spot BTC ETF exposure | Deepest among listed spot Bitcoin ETFs | Lowest practical friction for large or active orders | A large fee cut by a rival or sustained outflows from IBIT |
| FBTC | Strong alternative flow destination when investors want Fidelity custody | Usable, but thinner than IBIT | Good for normal allocation orders | If Fidelity custody becomes the main investor concern |
| ARKB | Can attract fee-aware buyers and ARK brand followers | Secondary | More sensitive to order size than IBIT | Fee competition or stronger marketing flows |
| BITB | Fee-sensitive and crypto-native investor appeal | Secondary | More sensitive to order size than IBIT | If low-fee positioning becomes the main decision factor |
Comparison Checklist
- Choose IBIT if the position may use options, covered calls, puts, or frequent rebalancing.
- Choose FBTC if the portfolio already has Coinbase-custodied crypto ETF exposure and needs custody diversification.
- Choose BITB or ARKB only after checking the live bid-ask spread for the intended order size.
- Do not split across four ETFs just for ticker variety; split only if custody, fee, or tax-lot management has a real purpose.
IBIT, FBTC, ARKB, And BITB Product Overview
IBIT is BlackRock's iShares spot Bitcoin ETF on Nasdaq and has become the scale benchmark for U.S.-listed Bitcoin ETF exposure. FBTC is Fidelity's spot Bitcoin ETF on Cboe BZX and is most important because its custody chain runs through Fidelity Digital Asset Services. ARKB is the ARK 21Shares product, also on Cboe BZX, with a lower 0.21% fee and ARK brand recognition. BITB is Bitwise's NYSE Arca product with a 0.20% fee and a crypto-native sponsor profile. The four funds all track spot Bitcoin, but they are not identical wrappers.
Core Fee, Custody, Liquidity, And Options Comparison
The core comparison is not just expense ratio. BITB's 0.20% and ARKB's 0.21% fees are lower than the 0.25% charged by IBIT and FBTC. On a $10,000 position, the annual fee difference between 0.20% and 0.25% is about $5; on a $1,000,000 position, it is about $500 before spreads and execution. IBIT can still be cheaper to trade for large or active orders if spreads and options liquidity matter. FBTC can be more useful when the investor wants non-Coinbase custody exposure.
Pros And Cons By Bitcoin ETF
IBIT's strengths are scale, liquidity, and options depth; its limitation is Coinbase-custody concentration if paired with other Coinbase-custodied crypto ETFs. FBTC's strength is Fidelity custody; its limitation is thinner options depth than IBIT. ARKB's strengths are the 0.21% fee and ARK/21Shares brand; its limitation is smaller scale. BITB's strength is the 0.20% fee and Bitwise's crypto specialization; its limitation is a smaller trading ecosystem.
Best Use Case And Final Recommendation
Choose IBIT for active trading, larger orders, options overlays, and default spot Bitcoin ETF exposure. Choose FBTC when custody diversification is the main objective. Choose BITB or ARKB for fee-sensitive buy-and-hold exposure after checking live spreads. For most investors, one primary Bitcoin ETF plus disciplined position sizing is cleaner than splitting across all four without a specific custody, tax-lot, or trading reason.
Common Questions
Which spot Bitcoin ETF is best for liquidity?
IBIT has the clearest liquidity and options-depth advantage in this group.
Which ETF has the lowest fee?
BITB charges 0.20%, ARKB charges 0.21%, while IBIT and FBTC charge 0.25%.
Which one diversifies custody best?
FBTC, because it uses Fidelity Digital Asset Services instead of Coinbase Custody.
Should investors buy all four?
Usually no. Multiple ETFs only make sense if they solve custody, tax-lot, or account-allocation needs.
Does a lower fee guarantee better returns?
No. Spreads, order size, tracking, and options use can offset a small fee difference.
Are these funds direct Bitcoin ownership?
No. They are securities that hold Bitcoin exposure through a fund wrapper.