Perpetual futures (perps) are derivative contracts that track a spot price without ever expiring. To keep their price anchored to spot, exchanges use a periodic payment called the funding rate. Long holders pay shorts when the perp trades above the index, and shorts pay longs when it trades below. The rate resets every 1, 4, or 8 hours depending on the venue.
Because each exchange computes its own funding rate from its own order book, the rates diverge. On any given hour, BTC perpetual on Binance might pay +0.01% per 8 hours while Hyperliquid pays −0.003%. Annualized, that's a 14-percentage-point gap — and you can capture it without taking any directional risk.
The Mechanic in One Sentence
Open equal-size positions on both venues in opposite directions: long the leg where funding pays you (the cheap side), short the leg where funding charges you (the rich side). Price moves cancel out across the two legs. You're left collecting the funding-rate gap, accrued every settlement window.
Worked Example
Suppose BTC trades at $80,000 and you have $20,000 to deploy. On Hyperliquid the next 8-hour funding window pays −0.012% to longs (negative funding = longs receive). On Binance it pays +0.014% (longs pay, shorts receive). You want to be long on Hyperliquid and short on Binance.
- Open a long position of $10,000 (= 0.125 BTC) on Hyperliquid
- Open a short position of $10,000 (= 0.125 BTC) on Binance
- Wait 8 hours. Hyperliquid credits 0.012% × $10,000 = $1.20. Binance credits 0.014% × $10,000 = $1.40.
- Total accrued: $2.60 per 8-hour window. Annualized (×1095): ≈ 28.5% APR on $10,000 deployed per leg.
Why This Isn't a Free Lunch
Three real costs eat into the headline number, and ignoring them is the most common beginner mistake:
- Entry and exit fees on both legs. A round-trip on most CEX perps costs 4–6 bps (0.04–0.06%) total. Aggressive DEXs like Lighter and Orderly run at 0 bps maker.
- Slippage on entry. If the order book is thin or your size is large, you pay above the mid price on the long leg and sell below on the short leg.
- Funding rate changes. The 28.5% APR holds only as long as both rates stay where they are. Spikes mean-revert; what looks like 200% APR for one hour can flip to −50% the next.
How to Find Real Opportunities
A naive screener that sorts by current funding rate will lead you straight into the highest-volatility, lowest-liquidity markets — where slippage destroys the headline APR. Three filters that help:
- Open interest above $1M on both legs. Less than that and your $10K position will move the mark.
- 24h volume above $500K on both legs. You need to be able to exit, not just enter.
- Stability score (coefficient of variation over the past 7d). Volatile rates revert; persistent gaps are the ones that pay.
Next Steps
Once you understand the mechanic, two paths to explore: stacking DEX points on the long leg (Hyperliquid, Aster, Lighter all have active campaigns — see our airdrop guide), and price arbitrage (a related but distinct trade where you capture mark-price convergence between two venues quoting the same asset differently).