Crypto Futures Arbitrage: Funding, Basis Basics, Fees, and Real Risks

What Futures Arbitrage Means in Crypto

Arbitrage seeks profit from price or carry differences between related instruments.

In crypto, common forms tie spot to perp, or perp across venues.

• Basis = futures price minus spot price
• Funding = periodic payment between longs and shorts on perps
• Cross-exchange = same contract priced differently on two platforms
• None are risk-free after fees and execution

Cash-and-Carry: Long Spot, Short Perp

When perp trades above spot, short perp and long spot can capture positive basis and funding.

The trade hedges direction — edge is carry minus costs.

• Long spot = own coin or equivalent exposure
• Short perp = offset delta on perpetual
• Profit when funding paid to short plus basis convergence
• Loss when basis widens against you or funding flips

Funding-Only Arb Mindset

Some traders focus purely on funding when rate stays elevated.

Delta-neutral hedge still needs both legs filled at fair prices.

• High positive funding — shorts often receive from longs
• Rate changes every interval — edge is not locked forever
• Crowded arb compresses rate faster than models assume
• Margin on short perp must survive volatility spikes

Fee Stack on Two Legs

Arb has at least two trade fees — often four if you enter and exit both legs.

Spreadsheet edge must exceed sum of fees, spread, and transfer.

• Spot buy fee plus perp sell fee on open
• Reverse on close — taker on both legs is conservative
• Withdrawal and deposit if legs sit on different exchanges
• Internal transfer cheaper than on-chain when same group

Basis Risk and Convergence Timing

Basis can widen before it narrows.

Margin calls hit on the losing leg while the winning leg is locked elsewhere.

• Mark-to-market loss on short perp if price rips
• Spot leg gains — but margin is per product, not netted everywhere
• Convergence timing unknown — carry must pay while you wait
• Delivery dates on dated futures add roll cost

Cross-Exchange Perp Arb

Buy perp cheap on venue A, sell rich on venue B.

Requires capital on both sides and fast balanced fills.

• Fill lag leaves naked delta briefly — model worst case
• Withdrawal queues delay rebalancing
• Different mark methods can force unequal liquidations
• Regulatory and account access differ by region

Operational Risks Beyond the Formula

Exchange downtime, API errors, and auto-deleveraging break neat arb.

• ADL can close profitable hedge leg first
• Maintenance margin rises in volatility — add buffer
• Stablecoin depeg hits spot leg valuation
• Smart routing bots compete spreads to minimal

Sizing and Margin Buffer

Arb is low directional edge but not zero margin stress.

Undersized buffer gets liquidated on one leg while hedge remains.

• Keep extra collateral on short perp side
• Monitor distance to liquidation on both venues
• Reduce size when funding turns against position
• Stress test for 10% adverse move on perp leg

Quick Summary

Crypto futures arbitrage harvests basis and funding with hedged legs.

Fees on every leg, transfer cost, and margin stress decide real profit.

Compare all-in costs across venues before deploying arb capital.

• Common form: long spot, short perp
• Sum fees on open and close for both legs
• Basis can widen before convergence — buffer margin