Spot Bitcoin ETFs Compared: IBIT vs FBTC, ARKB and BITB Fees

IBIT and FBTC are both US-listed spot bitcoin ETFs that hold real bitcoin, and as of November 2026 both state a 0.25% sponsor fee, against 0.21% for ARKB and 0.20% for BITB. The bigger differences between the four are who keeps the coins, which price benchmark values them and how much money each fund holds. This guide compares them from each issuer's own fund page and its SEC filings, and it names no winner, because the right fund depends on how long you hold, who you trust with custody and how much you trade.

What a spot bitcoin ETF is

A spot bitcoin ETF is a fund whose shares trade on a stock exchange and whose assets are bitcoin itself, not futures contracts. You buy and sell shares through a brokerage account, and the share price follows the value of the bitcoin the fund holds, minus its fee. The US Securities and Exchange Commission cleared the way on January 10, 2024, when it approved the applications of 11 spot bitcoin products to list on NYSE Arca, Nasdaq or Cboe BZX.

How it differs from owning bitcoin yourself

The shares give you price exposure to bitcoin, not bitcoin. The practical differences:

• Custody. A fund's bitcoin sits with a third-party custodian the fund hires. You hold shares, not private keys, so the idea behind not your keys, not your coins cuts both ways: you carry no key-loss risk, and you also cannot move the coins.
• Trading hours. Shares trade when the exchange is open. Bitcoin itself trades around the clock.
• Fees. A fund charges an annual sponsor fee on the bitcoin it holds. Owning bitcoin directly has no annual fee, though exchange and network fees apply when you buy or send.
• No withdrawal of coins. The funds create and redeem shares only with large institutions called authorized participants. Fidelity's filing says its trust "sells and redeems Shares only with Authorized Participants in exchange for bitcoin or cash." An ordinary shareholder sells shares on the market for dollars and receives no bitcoin.
• A brokerage account. You need an account at a broker that offers the fund.

If you want coins you can control, see the site's guides to buying bitcoin and to self-custody. The ETF is a different product, not a cheaper route to the same thing.

The four funds side by side

Fees, custodians and benchmarks come from each issuer's fund page or SEC filing; the net asset dates differ because the sources do. Fees and holdings change, so check the issuer page before acting. The ARKB page lists a custodian group rather than one name, and says it used the CME CF Bitcoin Reference Rate before switching to the FTSE Bitcoin Index on August 27, 2026.

Which differences matter to whom

None of the four is the best in every respect, and these are the differences a reader can weigh against their own situation.

If you plan to hold for years, the annual fee compounds. A gap of 0.05 percentage points on a $10,000 position is $5 a year, which is small, but it applies every year and to a larger balance as the position grows. Check the current fee on the issuer page, and check whether a fee waiver applies, since some funds have used temporary ones. BlackRock's filing for fiscal 2024 describes a temporary reduction of IBIT's fee to 0.12% on the first $5 billion of assets through January 10, 2025; IBIT's 10-Q for September 30, 2026 reports no fees waived in the nine months ended that date.

If custody arrangements matter to you, the funds differ. FBTC's custodian is an affiliate of its sponsor, Fidelity. IBIT and BITB use Coinbase's custody entity. ARKB spreads its coins across three custodians. Relying on a single custodian and holding the coins with an affiliate of the sponsor are two separate considerations, and the four funds handle them differently.

If you trade often or in size, liquidity matters more than a few hundredths of a percent. Fund size is one rough guide to how much trading a fund sees, and the table shows IBIT holding the most assets by a wide margin. Size is not a guarantee of tight pricing, so look at the spread between buy and sell prices in your own broker.

If you want to compare valuation methods, the benchmark is the rate a fund uses to value its bitcoin each day. IBIT and BITB use a CME CF rate, Fidelity uses its own, and ARKB moved from the CME CF rate to the FTSE Bitcoin Index on August 27, 2026. A different benchmark can produce small differences in the daily value, not different holdings.

IBIT vs FBTC

Because these two are searched together most, here is the short version. Both state a 0.25% fee. IBIT holds several times the net assets of FBTC in the table above, though the two figures are dated five weeks apart. IBIT's custodian is Coinbase Custody; FBTC's is Fidelity Digital Assets. IBIT lists on Nasdaq and FBTC on Cboe BZX, and FBTC values its bitcoin on Fidelity's own reference rate while IBIT uses the CME CF rate. Which of those differences is worth anything depends on the reader.

How shares are created and redeemed

The shares you trade are not issued one at a time. IBIT's 10-Q for September 30, 2026 says the trust "issues and redeems Shares only in aggregations of 40,000 Shares (a 'Basket')", and Fidelity's says FBTC deals "only in blocks of 25,000 Shares (a 'Basket')". IBIT's filing says only registered broker-dealers that have entered into an agreement with the sponsor, called authorized participants, can place orders for baskets, and Fidelity's says its trust deals only with authorized participants. IBIT's filing says the trust is authorized to create and redeem shares with them "on an in-kind basis", meaning against bitcoin itself, and Fidelity's says its trust deals with them "in exchange for bitcoin or cash". This is the route by which the supply of shares follows demand, and it is why a shareholder has no direct line to the fund's coins.

Costs and timing beyond the sponsor fee

The sponsor fee is the one cost the fund charges, and IBIT's 10-Q describes it as the trust's only ordinary expense for the period the report covers. It is not the whole cost of holding shares. Your broker may charge a commission, and every trade crosses the spread between the price buyers bid and sellers ask. Fidelity's filing also warns that "Shares may trade in the secondary market at prices that are lower or higher relative to the Trust's NAV per Share", so the price you get can sit above or below the value of the bitcoin behind each share. Neither filing gives a figure for commissions or spreads, which depend on your broker and on the moment you trade.

Timing differs from owning bitcoin too. Fidelity's filing refers to regular trading hours of 9:30 a.m. to 4:00 p.m. Eastern, and both filings say the net asset value for a normal trading day is released after 4:00 p.m. Eastern. Bitcoin trades through nights and weekends, so a move outside those hours reaches the shares only when the exchange reopens.

What happens if a fund winds down

IBIT's filing discusses this as a risk. It says that if the SEC or a federal court determined the trust's assets include securities, the sponsor "may nevertheless decide to terminate the Trust, in order, if possible, to liquidate the Trust's assets while a liquid market still exists", and that if the sponsor or trustee chose not to meet the extra regulatory requirements that would follow, "the Trustee will terminate the Trust." It warns that "any such termination could result in the liquidation of the Trust's bitcoin at a time that is disadvantageous to Shareholders." The filing describes liquidation of the bitcoin, not a handover of coins to holders. The FBTC filing read for this article does not describe termination, so the trust agreement and prospectus are where to look for any fund.

Availability outside the US

These funds are listed on US exchanges and bought through brokerage accounts. A reader in another country may be able to reach them only if a local broker offers US-listed ETFs, and that depends on the broker and on local rules, which this article cannot say for any particular country. The site's country guides cover what is available for buying bitcoin directly where you live.

Risks to keep in mind

The fund's price moves with bitcoin, so you can lose money quickly. This article is editorial information, not investment advice, and the site's rankings and comparisons are not for sale. To convert a dollar amount into bitcoin at today's price, use the site's bitcoin converter.