Pairs Trading 101
Pairs trading is a market-neutral strategy: instead of betting a coin goes up or down, you bet that the relationship between two coins reverts to its norm.
The idea
Some pairs of assets move together over time. When their price relationship stretches unusually far apart, a pairs trader:
- Shorts the rich leg (the one that has run ahead), and
- Longs the cheap leg (the one that has lagged),
sized so the combined position is roughly insensitive to the overall market direction. If the relationship snaps back, the trade profits regardless of whether the market went up or down in the meantime.
The spread
The relationship is measured as a spread:
spread = price_A − β · price_B
where β (the hedge ratio) is estimated from historical data. A well-behaved spread oscillates around a stable mean — that oscillation is what the strategy trades.
Why perpetuals
Perpetual futures make both legs easy: shorting is as simple as longing, leverage is native, and funding payments can even work in your favor (see Funding & Fees).
One coin, one pair
On this terminal, a coin can be a leg of at most one of your open pairs — if you hold BTC-ETH, every other BTC-something and ETH-something pair is unavailable until it closes.
The coin itself is not locked. You can hold it outright, trade it yourself on Hyperliquid, and add to or trim your pair — you are never locked into the fitted hedge ratio. The desk tracks your pair by its own fill ledger (the orders it placed for you), so your personal position in the same coin stays yours: a pair exit closes the pair's legs and touches nothing else.
That ledger is the pair's whole book — and it comes with an honest limit. A perpetuals account nets each coin into a single number, so once you trade a pair-leg coin yourself, the venue total is the pair's leg plus your personal residual, and no one — including the desk — can tell "you trimmed the pair" apart from "you traded the coin personally." The desk never guesses: exits size only up to the venue holding that points the pair's way, drift shows as a neutral residual chip on the row (holds less / holds more / points against), and a row is closed for you only when the venue provably holds nothing in a leg — as liquidated when the venue's own fill flag confirms a liquidation, otherwise as manual_venue.
What it will not do is run two hedge-weighted pairs through the same coin. A perpetuals account nets each coin into a single position, and two overlapping pairs would merge into one number that no dashboard could honestly split back apart. Rather than show a guess, the desk refuses the state: conflicting pairs are greyed in the Book with the owning pair named, and they unlock the moment it closes. One consequence of the rule is arithmetic, not a malfunction: every open pair claims two coins exclusively, so popular-coin pairs (everything-vs-BTC, everything-vs-ETH) crowd each other out early, and a tracked universe of ~148 coins supports at most ~74 simultaneous disjoint pairs.
The risks
- The relationship can break. Cointegration is statistical, not guaranteed. Stops exist for this reason.
- Funding can bleed. A position held through unfavorable funding pays a running cost.
- Both legs carry liquidation risk individually, even if the combined position is market-neutral.