Spot against the perpetual
Spot-futures arbitrage: trading the basis back to its norm
A coin’s spot price and its perpetual almost never match, and every pair has its own usual gap that holds for weeks. The VVARB screener learns that norm for thousands of pairs and shows the moments a pair moves away from it: what to buy, what to short, at what price and when to close.
Free after sign-up, on data six hours old. No bank card needed.
What spot-futures arbitrage is
The basis is the difference between a perpetual’s price and the spot price of the same coin. Funding pulls them together, but not to zero: every pair has its own usual gap, and it holds for weeks. Of five thousand liquid pairs, about half live with a basis clearly away from zero. So a price gap on its own means nothing: 0.3% is normal for one pair and a rare deviation for another.
Spot-futures arbitrage trades the deviations from that norm. If the perpetual has become unusually dear against spot, you buy the coin on spot and short the perpetual for the same amount. The position is delta-neutral: the coin rising or falling barely affects the result. The money comes when the basis returns to its usual size and both legs are closed.
This is not classic cash and carry, where the position is held for funding. Here funding is the cost of waiting and the profit is the basis returning to normal. That is how the screener counts it: funding is added or deducted over your holding time, never presented as the source of income.
A worked example
| The basis returns to normal: spot $50.10, perpetual $50.20 | |
| Spot: 20 × ($50.10 − $50.00) | +$2.00 |
| Perpetual short: 20 × ($50.40 − $50.20) | +$4.00 |
| Fees: spot 0.1% in and out, perpetual 0.05% in and out | −$3.01 |
| Funding over a day of waiting (can be positive too) | −$0.30 |
| Total | +$2.69 |
| On about $1,504 of capital (spot $1,000 + perpetual margin at leverage 2) | ≈ 0.18% |
The move from 0.8% back to 0.2% made $6, and more than half of it went on fees and funding. That is why the screener shows not just the deviation but what is left after every deduction and how much money the trade really needs.
What the screener shows
- The usual norm of every pair. The screener measures what the basis of this pair usually is and compares the present with it.
- The deviation in percent and in sigmas: how unusual the move is for this pair, not in general.
- A basis chart with the norm and the two-sigma band: where the pair is now and where it usually lives.
- The plan right under the chart: what to buy, what to short, the entry price and the basis to close at.
- How much money it really takes and how far the price can rise before the perpetual leg is force-closed.
- Funding as the cost of waiting over your chosen holding time, not as promised income.
- The direction that needs a borrowed coin is off by default and marked separately: selling spot without the coin is only possible with a margin loan.
How to use the screener
Sign up
A free account opens the screener straight away with every calculation, on data six hours old. No bank card needed.
Pick a pair that deviates
Look for pairs two sigmas or more away from their norm, with enough turnover on both legs.
Check the numbers after deductions
See what is left after fees and funding over the expected time, and how much capital it takes.
Open both legs
Buy the coin on spot and short the perpetual for the same quantity. If the perpetual has become cheaper than spot, the direction is reversed and needs a borrowed coin.
Close when it is back to normal
When the basis is back to its usual size, close both legs. The plan shows the basis to close at.
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What eats the profit
| Risk | What happens | What the screener does |
|---|---|---|
| Spot fees | Spot fees are higher than futures fees and eat a visible part of the return | Deducts both legs’ fees from the result |
| A slow return | The basis takes days to come back while funding keeps running | Counts funding over your holding time |
| The norm shifted | The pair changed regime and the old norm no longer holds | Recalculates the norm on fresh data and shows the chart |
| Short liquidated | The coin jumped and the perpetual’s collateral ran out | Shows how far the price can rise before closing |
| Borrowing the coin | The reverse direction needs a borrowed coin, which costs more and carries more risk | Turns it off by default and marks it separately |
A return to the norm is statistics, not a guarantee. A pair can move further away before it comes back, and the norm itself can change. Keep spare collateral on the perpetual leg.
Free and with a subscription
| Free | Subscription | |
|---|---|---|
| Pair norms, deviations, charts, plans | Yes | Yes |
| Data | 6 hours delayed | Live |
| Order book and depth | - | Yes |
| Telegram alerts | - | Yes |
Free access has no time limit: you can study how pairs move away and come back on real data. A subscription is for entering at the moment of the deviation.
Questions about spot-futures arbitrage
What is the basis in crypto?
The difference between a perpetual’s price and the spot price of the same coin, usually in percent. A positive basis means the perpetual is dearer than spot, a negative one that it is cheaper.
How is this different from cash and carry?
In cash and carry the "spot plus short perpetual" position is held for funding. Here the profit is the basis returning to the pair’s usual norm, and funding is treated as the cost of waiting.
Why does every pair have its own norm?
Funding, demand for leverage, liquidity and the venue’s quirks differ for every coin. So a 0.3% basis is normal for one pair and rare for another. The screener measures the norm separately for each pair.
What does a deviation in sigmas mean?
A sigma is the usual spread of this pair’s basis. A deviation of two sigmas or more is rare and returns to the norm more often than small wobbles do. But it is statistics, not a guarantee.
Do I need to borrow the coin?
Not for the main direction: you buy the coin on spot and short the perpetual. Borrowing is only needed for the reverse direction, when the perpetual is cheaper than spot. The screener turns that off by default.
Do I need to move the coin between exchanges?
No. Both legs open where both spot and the perpetual trade, and the coin never moves.
What is the difference between free access and a subscription?
Free access opens the same screener with every calculation, on data six hours old. A subscription adds live data, the order book and Telegram alerts.
More on the subject: spot-futures and the basis, what the funding rate is, the delta-neutral strategy and the risks of arbitrage.
Start with free access
Pair norms, deviations and plans on real data six hours old, with no time limit. A subscription from $19.92 a month opens live data, the order book and Telegram alerts.