What is funding rate arbitrage?
Funding rate arbitrage — also called the spot-perp carry trade — is a market-neutral crypto trading strategy that earns the perpetual futures funding rate by simultaneously holding a long spot position and a short perpetual position on the same asset. Because the two legs offset each other on price movement, the trade has minimal directional exposure and collects the funding rate as yield. Binance, Bybit, OKX, and most major venues settle funding every 8 hours; Hyperliquid and dYdX v4 settle every hour. Funding is paid from the losing side of the dominant positioning — when funding is positive, longs pay shorts (you profit on the short leg); when negative, shorts pay longs (you'd flip to long perp + short spot, the reverse-basis trade).
The net APR formula
APR = (funding_rate × 8,760 / interval_hours) − (maker_fee × 4 × annualization_factor). The 8,760 is hours per year. Divide by your exchange's interval to get settlements per year. Multiply by the rate to get gross APR. Subtract fees: four events per cycle (open spot + open perp + close spot + close perp) at your maker-fee tier. For a 0.01% 8-hour rate at 0.02% maker fee, gross APR = 10.95%; fee drag on a 30-day hold is 0.08% of notional = 0.97% annualized; net APR ≈ 9.98%. For a 0.05% 8-hour rate (typical altcoin bull-regime funding), gross APR = 54.75% and net APR ≈ 53.8%.
Worked example: $10,000 BTC-USDT on Binance
Scenario: BTC-USDT funding rate on Binance is 0.02% per 8 hours, you deploy $10,000 notional on each leg (long spot, short perp), hold for 30 days, pay 0.02% maker fees. Gross funding per settlement = $10,000 × 0.0002 = $2. Settlements in 30 days = 90 (30 × 3 per day). Gross funding over hold = $180. Fees = $10,000 × 0.0002 × 4 = $8 total. Net PnL = $172. Annualized = ($172 / $10,000) × (365 / 30) × 100 = 20.9% net APR. Sharpe's calculator at /arbitrage/calculator computes this instantly for any rate, size, interval, fee, and holding period.
Execution: six-step workflow
Step 1 — scan: open the /funding-rates/highest-lowest, sort by APR, filter for OI above $10M to ensure you can size meaningfully without slippage. Step 2 — verify spread: check the spot-perp basis on your target exchange is tight (< 10 bps) so execution is clean. Step 3 — place both legs simultaneously as maker limit orders to pay the lower fee tier. Post them within a few seconds of each other to minimize directional exposure during the fill. Step 4 — time entry 30–60 minutes before the next funding settlement so your first payment captures near-full value. Step 5 — monitor drift: if funding rate halves mid-trade, exit and redeploy; if short-leg liquidation buffer tightens, add margin or reduce size. Step 6 — close both legs together when your target yield is captured or the opportunity decays.
Risk management
Three risks dominate. First, funding normalization — extreme APRs typically decay within hours as liquidity providers arbitrage the dislocation; model your realistic holding period at the calculator. Second, short-leg liquidation — the perpetual leg can wick sharply higher even when spot is flat. Use isolated margin with 3–5× the maintenance margin buffer (e.g., if maintenance is $500 on your short, keep $2,000+ in the isolated wallet). A 30–50% price spike should leave you above maintenance. Third, exchange counterparty risk — especially on smaller venues. Diversify across 2–3 exchanges rather than concentrating capital on one.
When funding arbitrage goes wrong
The classic failure mode is the 'rug on the short leg' — funding rate was paying 100% APR, you enter a $20K spot-perp trade, and 20 minutes later a squeeze wicks the perp up 40% forcing your short to liquidate. Your spot leg has the offsetting gain but unrealized; the realized loss on the short leg can exceed it net of fees. Mitigate with smaller position sizing, isolated margin, and pre-set liquidation alerts. Another common failure: entering at peak funding, which mean-reverts toward zero within hours as the same arbitrage you're running compresses the dislocation. The calculator's break-even column shows how low funding can go before your trade becomes unprofitable.
Advanced: cross-exchange and basis variants
Cross-exchange funding arbitrage captures the rate spread between exchanges: long perp on the negative-funding venue, short perp on the positive-funding venue. No spot leg required. Captures the net spread, typically 0.01–0.05% per 8-hour settlement. Cash-and-carry basis arbitrage uses dated futures rather than perps: long spot + short quarterly future, collecting the annualized basis at expiry when futures converge to spot. In bull markets CME BTC basis trades have yielded 10–15% annualized with zero funding-rate volatility. Stablecoin network choice matters for cross-exchange — USDT on TRC-20 is cheapest for transfers; USDC on Solana is fastest.