Which ETF has a lower expense ratio, FBTC or ARKB?

ARKB has the lower expense ratio at 0.21% vs 0.25% for FBTC.

Which ETF is larger by assets under management, FBTC or ARKB?

FBTC is larger by AUM. FBTC has approximately $10.8B in assets versus $2.1B for ARKB (based on most recent available data).

Can I hold both FBTC and ARKB in my portfolio?

Yes. Both FBTC and ARKB can be held simultaneously through most brokerage accounts. However, since both track the spot price of Bitcoin, holding both in large quantities results in concentrated and highly correlated exposure. Investors typically choose one spot Bitcoin ETF rather than diversifying across multiple to keep costs low.

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FBTC vs ARKB

Head-to-head Bitcoin ETF comparison - expense ratios, AUM, performance, and more

Quick Answer

ARKB has the lower expense ratio at 0.21% versus 0.25%. Fidelity's FBTC is roughly 5x larger by assets ($10.8B vs $2.1B). ARK 21Shares's ARKB uses Coinbase Custody (primary, with BitGo added) for Bitcoin custody, while FBTC uses Fidelity Digital Assets.

FBTC

Fidelity Wise Origin Bitcoin Fund ETF

IssuerFidelity

Expense Ratio0.25%

AUM$10.8B

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ARKB

ARK 21Shares Bitcoin ETF

IssuerARK 21Shares

Expense Ratio0.21%

AUM$2.1B

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At a Glance

Lower Fee

ARKB

Larger AUM

FBTC

More Liquid

Tied

Best YTD

Tied

Full Comparison

Metric	FBTC	ARKB
Expense Ratio	0.25%	0.21% Winner
AUM	$10.8B Winner	$2.1B
Price	$56.53	$21.54
YTD Return	-27.70% Tie	-27.69% Tie
1-Year Return	-44.93% Tie	-44.91% Tie
Avg Daily Volume	4.4M Tie	3.6M Tie
Custodian	Fidelity Digital Assets	Coinbase Custody (primary, with BitGo added)
Issuer	Fidelity	ARK 21Shares
Inception Date	Jan 11, 2024	Jan 11, 2024
Exchange Listed	Cboe BZX Exchange	Cboe BZX Exchange
SEC Registered	Yes	Yes

Key Differences

Different Custodians

FBTC holds its Bitcoin with Fidelity Digital Assets, while ARKB uses Coinbase Custody (primary, with BitGo added). Custodian choice affects your exposure to counterparty risk and the operational security model protecting the fund's Bitcoin.

Which Is Right For You?

FBTC is best for:

Fidelity account holders seeking low-cost direct Bitcoin exposure via a regulated spot ETF

ARKB is best for:

U.S. investors seeking low-cost direct Bitcoin exposure through a dual-custodied spot ETF

21Rates Take

FBTC and ARKB are close competitors with similar expense ratios, both significantly cheaper than GBTC. FBTC is Fidelity's product, offering deep integration with Fidelity brokerage accounts and the familiarity of a major financial institution. ARKB is a collaboration between ARK Invest and 21Shares, appealing to investors drawn to ARK's innovation-focused brand. Both use institutional cold-storage custody. For investors without a strong brand preference, the choice may come down to your existing brokerage platform and whether access to ARKB options matters to your strategy.

Reviewed by 21Rates Editorial on Jul 20, 2026

Frequently Asked Questions

What is the difference between FBTC and ARKB?

FBTC is issued by Fidelity and charges a 0.25% expense ratio, while ARKB is issued by ARK 21Shares at 0.21%. Both are spot Bitcoin ETFs that hold physical Bitcoin. They differ in issuer, custody arrangements (FBTC uses Fidelity Digital Assets; ARKB uses Coinbase Custody (primary, with BitGo added)), and overall fund scale.

Which has the lower expense ratio, FBTC or ARKB?

ARKB has a lower expense ratio at 0.21% versus 0.25% for FBTC.

Which ETF has more assets under management?

FBTC is the larger fund by AUM at $10.8B versus $2.1B for ARKB.

Can I hold both FBTC and ARKB at the same time?

Yes. Both funds can be held in most brokerage accounts simultaneously. However, since both track Bitcoin, holding both creates highly correlated exposure. Most investors choose one fund to keep costs and complexity low.

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Market data (price, AUM, volume, returns) is updated up to 3 times daily from live market sources. Expense ratios and fund details are sourced from fund prospectuses and issuer disclosures.

Data as of Aug 8, 2026.

This comparison is for informational purposes only and does not constitute investment advice. Bitcoin ETFs are subject to market risk including the potential loss of principal. Past performance does not guarantee future results.