Between October 2021 and January 2024, an American investor who wanted bitcoin exposure through a fund could only buy one that did not own any bitcoin. That three-year gap is the clearest available natural experiment in why fund structure matters, and it is worth understanding even now that the argument has been settled.
The two structures
| Spot fund | Futures fund | |
|---|---|---|
| What the fund holds | The cryptoasset itself, with a custodian | Exchange-traded futures contracts, plus cash collateral |
| Tracks the coin price | Closely, minus fees | Approximately, minus fees and roll cost |
| Main hidden cost | Bid-offer spread | Roll cost when the curve is in contango |
| Counterparty exposure | Custodian | Futures clearing house and broker |
| Regulatory history | US approval January 2024; UK retail still barred from funds | US approval October 2021, under the 1940 Act |
| UK retail access | Not permitted as a fund; permitted as a London-listed note | Not permitted — falls inside the derivatives restriction |
| Suited to | Holding exposure over time | Short-horizon positioning by investors who can use derivatives |
Structural characteristics from fund prospectuses. UK access position reflects FCA policy as at September 2026: the restriction on selling cryptoasset derivatives to retail consumers remains in force.
Why futures funds existed first
The sequence was not an accident of market demand. It was regulatory.
The SEC spent years rejecting spot bitcoin fund applications on the grounds that the underlying spot market was susceptible to manipulation and lacked a surveillance-sharing agreement with a regulated market of significant size. It was, however, willing to approve funds holding CME bitcoin futures, because the CME is a regulated exchange under CFTC oversight. The first US bitcoin futures ETF listed in October 2021 under the Investment Company Act of 1940.
So for three years investors got a fund built on a regulated derivative of an asset the regulator would not let them hold through a fund. The logic was internally consistent and the outcome was peculiar. It ended in the courts rather than through a change of mind, and spot funds listed in January 2024.
Roll cost, explained without jargon
A futures contract has an expiry date. A fund that wants to keep its exposure cannot hold one indefinitely — it has to sell the contract that is about to expire and buy a later one. That operation is called the roll, and it happens every month, mechanically, regardless of what anyone thinks about the price.
Here is where it costs money. If the later contract is priced higher than the expiring one, the fund sells low and buys high every single month. The size of that gap is a real cost, borne by shareholders, and it appears nowhere in the expense ratio.
Why the expense ratio lies about futures funds
A futures fund quoting a 0.95% expense ratio may deliver a result several percentage points behind the asset over a year in a persistently contangoed market. The fee is accurate; it is not measuring the cost that matters. The figure to look at is tracking difference against the spot price, not the expense ratio. Past performance is not a reliable indicator of future events.
Contango and backwardation
Two words for the two possible shapes of a futures curve, and the only jargon on this page you genuinely need.
Contango is when contracts further out are more expensive than nearer ones. This is the normal state for an asset that costs something to hold, and it has been the common state for bitcoin futures. In contango, rolling costs you.
Backwardation is the reverse: later contracts priced below nearer ones. In backwardation, rolling actually pays you. It happens, generally when there is urgent demand for immediate delivery, but it has not been the persistent state of crypto futures.
The practical consequence is asymmetric. A futures fund held through a contangoed period leaks value relative to the spot asset. A spot fund held through the same period leaks only its fee. Over a long holding period, that difference compounds into something far larger than any fee-table comparison would suggest.
What "physically backed" means
In Europe and the UK the equivalent of a spot fund is a physically backed exchange traded note, and the phrase is doing precise work.
Physically backed means the issuing vehicle buys and holds the actual coin, one-for-one with the notes it has issued, through an independent custodian, with a security interest granted to a trustee on behalf of noteholders. Almost all the main London-listed bitcoin and ether products work this way — the iShares, Bitwise, 21Shares, WisdomTree, CoinShares, Invesco and Fidelity lines all hold the coin.
A synthetic product does not. It gets its exposure from a swap with a counterparty, which reintroduces exactly the kind of derivative exposure the physical structure was built to avoid. The word to look for in the Key Information Document is "physical"; the words to be wary of are "synthetic", "swap-based" and "enhanced".
Leveraged, inverse and short products
A large cluster of searches in this category is for 2x and 3x crypto funds, inverse products, and ways to short crypto through an ETF. We are going to deal with those directly rather than pretend they do not exist, because the honest answer is useful.
They are derivatives products. A leveraged or inverse fund cannot be physically backed, by definition — there is no way to hold 3x the bitcoin you have money for without borrowing or using swaps. That places these products squarely inside the category the FCA has restricted for UK retail consumers, and the regulator explicitly kept that restriction in place when it liberalised ETNs in October 2025.
Daily rebalancing does something people do not expect. A 3x daily fund delivers three times the daily return, not three times the return over a month or a year. Because the multiple resets each day, a volatile sideways market erodes the position even if the asset ends where it started. This is arithmetic, not an opinion, and it is disclosed in every one of these prospectuses. In an asset as volatile as bitcoin, the erosion is substantial.
They are built for a holding period measured in days. The issuers say so. Using them as a long-term expression of a view is a misuse of the instrument, and the people who do it generally discover this after rather than before.
On shorting crypto through a fund
There is no route for a UK retail investor. Inverse and short crypto products are derivatives and fall under the FCA restriction. Nor is there a workaround worth pursuing: an offshore account that permits the trade has generally taken you outside the UK regulatory perimeter altogether, with no FCA-supervised firm, no UK complaints route and no protections you would recognise.
Where UK rules draw the line
The line is cleaner than most people assume, and it is drawn around derivatives rather than around crypto.
- Physically backed cryptoasset ETN on a UK recognised investment exchange — permitted for retail since 8 October 2025.
- Spot crypto ETF listed in the US — not permitted for UK retail. It is a fund, not a note, and it sits outside the carve-out.
- Futures-based crypto fund — not permitted. Derivatives.
- Leveraged, inverse or short crypto product — not permitted. Derivatives.
- UCITS ETF holding crypto-related company shares — permitted, and always has been. It holds equities, not cryptoassets. See blockchain equity ETFs.
How to tell which one you are looking at
Thirty seconds of checking removes almost all the ambiguity.
Open the Key Information Document or factsheet and find the investment objective. A spot or physically backed product will say it holds the cryptoasset, and will usually name the custodian within the first page. A futures product will reference contracts, a roll schedule and a collateral policy. A leveraged one will state a daily multiple and, almost always, carry an explicit warning that it is not intended to be held for more than one day.
If the document is vague about what the product owns, that is itself the answer. Every legitimate issuer in this market states it plainly on the first page, because they are required to.
Spot and futures funds: questions
What is a spot crypto ETF?
A fund that holds the actual cryptoasset. If you own shares in a spot bitcoin ETF, the fund owns bitcoin, held by a custodian, in a quantity proportional to the shares in issue. The share price therefore tracks the bitcoin price directly, minus the fund's costs. "Spot" is the market term for immediate delivery of an asset, as opposed to a contract for future delivery — which is exactly what distinguishes it from a futures fund.
What does spot ETF mean in crypto, and why was it such a big deal?
It mattered because for three years the US permitted only futures-based bitcoin funds and refused spot ones. The SEC's stated concern was market manipulation in the underlying spot market. That position was overturned in court and the first spot funds listed on 11 January 2024. The significance was structural rather than symbolic: a spot fund creates real, continuous demand for the coin itself, because the fund must buy bitcoin every time it issues shares. A futures fund never touches a coin.
Are futures crypto ETFs worse than spot ones?
For holding exposure over time, they have historically been costlier, because of roll cost. When the futures curve is in contango — longer-dated contracts priced above nearer ones — the fund sells a cheaper expiring contract and buys a more expensive later one every month, and that difference is a drag that does not appear in the expense ratio. Crypto futures curves have spent a great deal of their history in contango. For short-horizon tactical use by investors who are permitted to hold derivatives, the calculation is different.
Can I buy a leveraged or inverse crypto ETF in the UK?
Not as a retail investor. These products achieve their exposure through derivatives, which puts them squarely inside the FCA restriction on selling cryptoasset derivatives to UK retail consumers — a restriction the regulator explicitly kept in place when it reopened access to ETNs in October 2025. Leveraged products also carry a structural feature many buyers misunderstand: daily rebalancing means that over any period longer than a day, the return is not the multiple of the asset's return.
Is a physically backed ETN the same as a spot ETF?
Economically they are close. Both hold the actual coin with a custodian, both track the spot price, and both create and redeem to keep the price honest. The difference is legal: a spot ETF is a fund and you own a share of its assets; a physically backed ETN is a debt instrument and you own a secured claim on the issuer. That distinction is the reason a UK retail investor can buy one and not the other. See ETF vs ETN vs ETP.
Sources & further reading
- SEC — Order approving spot bitcoin exchange-traded products, 10 January 2024
- Congressional Research Service — SEC approves bitcoin exchange-traded products
- FCA — Retail access to cryptoasset ETNs; derivatives restriction retained
Figures on this page were checked against the sources above on the date shown at the top of the article. Fund sizes, fees and product availability change; always confirm current numbers on the issuer's own factsheet or KID before acting.