How to Compare Bitcoin ETFs: Fees, Spreads, Tracking
All 12 US spot Bitcoin ETFs track the same asset — bitcoin — so their long-run returns will look very similar. The differences that matter are cost and market structure: what you pay each year, what you pay each time you trade, and how reliably the share price follows bitcoin. This guide is a framework for what to look at. It won't tell you which fund to pick — that's a decision for you (and, if you want one, a financial adviser).
Start with the expense ratio
The expense ratio is the annual fee, and it's the single biggest lasting difference between funds. Across the 12 spot ETFs it ranges from 0.14% (MSBT) to 1.50% (GBTC), with most funds clustered between 0.19% and 0.25% — including IBIT, the largest fund at roughly $65.7 billion in assets, at 0.25%. Because every fund holds the same underlying asset, a higher fee is mostly just a drag: there is no star manager earning it. For the full dollar math, see Bitcoin ETF fees explained.
Fund size and liquidity: why they matter
Size isn't about bragging rights — it determines how cheaply you can trade. The largest funds have enormous daily trading volumes, deep order books, and many competing market makers. That produces tight bid-ask spreads: the gap between what buyers will pay and sellers will accept is small, so you lose very little on each trade.
At the other end, some funds hold under $500 million in assets with much thinner trading. Their spreads can be several times wider, which is a cost you pay every time you buy or sell — and it can matter more than a small difference in expense ratios if you trade actively. When comparing, look at average daily volume and typical spreads, not just assets under management. Most brokers display the current bid-ask spread on the quote page, and fund factsheets often publish average spreads and daily volume — a 30-day average smooths out quiet days and gives a fairer picture than a single snapshot.
There's a compounding angle here too: a fund that is steadily gathering assets tends to get more liquid over time as volume grows and more market makers participate, while a fund stuck at a small size can stay expensive to trade indefinitely. That makes the asset trend — growing, flat, or shrinking — as informative as the current asset figure.
Tracking difference: does it follow bitcoin?
Tracking difference measures how closely a fund's returns match bitcoin's price over a period — usually shown as a 1-year figure in fund factsheets. The drag comes from the expense ratio plus smaller frictions: cash held for operations, the timing of creations and redemptions, and trading costs inside the fund. Among spot ETFs the differences are small, but they're worth checking because tracking difference captures the total cost of holding the fund, not just the headline fee.
Premium and discount to NAV
A fund's market price should sit very close to its net asset value (see What is a spot Bitcoin ETF? for why). Persistent premiums or discounts would signal that the arbitrage mechanism isn't working well — a red flag. In practice, today's large spot ETFs track NAV tightly; the cautionary tale is the old GBTC trust, which traded at deep discounts for long stretches precisely because it lacked a redemption mechanism. For current funds, glance at the premium/discount history: it should hover near zero.
Custodian and structure
Most US spot funds use Coinbase as their bitcoin custodian; Fidelity custodies its own fund's bitcoin itself. Custody arrangements, insurance, and the sponsor's operational track record are worth a look in the prospectus, even though failures have been absent so far. Also check whether the fund lends its bitcoin — most spot ETFs don't, but the prospectus is the place to confirm rather than assume. A related detail: some sponsors run multiple crypto products, which can mean shared operational infrastructure — neither good nor bad on its own, but worth knowing who is ultimately responsible for your fund's coins.
A checklist, not a pick
When you line the funds up side by side, work through these in order:
- Expense ratio — the recurring annual cost; ranges 0.14%–1.50%.
- Spread and volume — the per-trade cost; favors large, heavily traded funds.
- Tracking difference — the all-in measure of how well it follows bitcoin.
- Premium/discount history — should sit near zero for a healthy ETF.
- Custodian and sponsor — who holds the coins and who runs the fund.
- Asset trend — a fund steadily gathering assets tends to get more liquid over time, not less.
Run the funds through that checklist with live numbers in the comparison tool, which also includes a fee calculator so you can translate expense ratios into dollars for your own position size.
Related reading: Bitcoin ETF fees explained for the dollar math behind expense ratios, and How Bitcoin ETF flows work for what creations and redemptions tell you about demand.