Cash and Carry vs Funding Arbitrage: What's the Difference?.

Cash and carry pairs a spot holding with a short perp on the same asset: you own the asset, short the perpetual against it, and collect funding while fully hedged. Funding arbitrage pairs two perps on the same asset across two venues: long where the funding flow favors longs, short where it favors shorts, collecting the spread between the two rates. Both are delta-neutral constructions harvesting the same structural flow, and the difference in machinery, one spot leg versus two leveraged legs, drives every practical difference between them.

The risk difference is the important one. In cash and carry, the spot leg cannot be liquidated: it is the asset, fully paid, with no margin engine watching it. Only the perp leg carries liquidation risk, and a price rise that pressures the short perp simultaneously enriches the spot holding, so the position’s net value barely moves even while the margin on one leg needs management. Run it on a single venue that cross-margins spot against perps and the hedge is visible to one engine, tightening the construction further. Funding arbitrage has no such anchor: both legs are leveraged instruments on separate venues, marked by different engines against different references, with margin that cannot flow between them. Each leg can be liquidated independently, and the moments that threaten one leg are precisely the fast moves when the venues’ marks diverge, the failure anatomy in why delta-neutral positions still get liquidated.

The capital and yield difference runs the other way, which is why both trades exist. Cash and carry is capital-heavy: the spot leg is fully funded, so the funding you collect is yield on the whole position’s value, modest by construction, anchored near the structural baseline from what a normal funding rate is. Funding arbitrage posts margin rather than full value on both legs, so the same collected spread is a multiple higher as a return on capital, with the multiple purchased entirely by adding the liquidation exposure the carry trade does not have. Higher return on capital, same gross flow, new tail risk: that is the whole trade-off stated honestly.

Two further differences worth logging. Direction of availability: cash and carry in its standard form needs positive funding, and its inverted version on negative-funding markets requires borrowing the asset to short spot, putting the borrow rate, per funding versus interest versus borrow rate, in the middle of the math; funding arbitrage only needs two venues to disagree, in either direction, per why funding differs across exchanges. And settlement complexity: carry has one funding clock to manage, the cross-venue trade has two, usually mismatched, with everything that implies from how often funding is paid. The general rule that falls out: cash and carry is the trade for harvesting the baseline, funding arbitrage is the trade for harvesting dislocations, and the full honest assessment of both as yield sources is in funding harvesting.