Perpetual funding-rate arbitrage

You buy an asset on the spot market and open a short perpetual futures position of the same size. The two legs cancel each other's price exposure, and while funding is positive the short leg receives a payment from longs at every funding settlement. It is the crypto version of a cash-and-carry trade: you are paid to supply the short side of a market where demand for leverage is structurally long.

How it works

A perpetual future has no expiry. To keep its price anchored to the spot index, the venue runs periodic funding payments between longs and shorts. When the perp trades above the index, funding is positive and longs pay shorts. When it trades below, funding is negative and shorts pay longs.

Match the legs in coin units, not dollars. If BTC doubles, both legs double in dollar value together and the hedge holds without any adjustment.

Funding mechanics

The payment at each settlement is position notional multiplied by the funding rate. Notional is normally mark price times position size, so the dollar amount of funding rises and falls with price.

Most venues use a formula of the same shape: a premium component (how far the perp trades from the index, averaged over the interval) plus a clamped interest-rate component. On many major CEXs and on Hyperliquid the interest component is equivalent to 0.01% per 8 hours. That is why funding tends to sit at exactly that level in calm markets. Annualized, 0.01% per 8 hours is 10.95% APR on notional (0.01% × 3 × 365).

Settlement intervals differ by venue and by contract:

• Most major CEX perpetuals default to 8-hour settlement at 00:00, 08:00 and 16:00 UTC. Some contracts settle every 4 hours.
• Binance, OKX and Bybit shorten the interval automatically, down to hourly, when funding hits its cap or floor, and revert once it normalizes.
• Hyperliquid computes the rate on an 8-hour basis but settles one-eighth of it every hour. Its funding is capped at 4% per hour.

On a CEX you usually have to hold the position at the settlement timestamp to receive or pay. Check the contract specification for the interval, cap and floor before sizing a trade.

On-chain perps with different fee designs, such as those that charge borrow fees on top of or instead of funding, need their own cost model. Do not assume the CEX formula applies.

Where the yield comes from

The yield comes from demand for leverage. Most crypto derivatives traders want leveraged long exposure, and perps are the cheapest way to get it. When demand for longs exceeds the natural supply of shorts, the perp trades above spot and funding turns positive. The short side of this trade is effectively lending dollars to leveraged longs, and funding is the interest.

Three forces set the level:

1. Baseline. With the interest component at 0.01% per 8 hours, funding settles near 10.95% APR on notional whenever the premium is small. That describes a normal market; it is not a guaranteed floor.
2. Bull-market premium. In strong uptrends, long open interest grows faster than short open interest. The premium widens and funding can run at several times baseline for weeks.
3. Competition. Every dollar of delta-neutral capital adds to the short side and compresses the premium. Tokenized versions of this trade, such as synthetic dollars backed by hedged spot positions (Ethena's USDe is the best-known), have made it much more crowded than it used to be.

Your return on capital is lower than the funding rate on notional, because part of your capital sits in the margin account instead of the spot leg.

Worked example

Assume the following. These are illustrative numbers, not current market data.

• Capital: $10,000.
• Spot leg: $6,500 of BTC. Perp margin: $3,500 in stablecoins. Short notional: $6,500, about 1.86x leverage on the short leg.
• Funding averages 0.01% per 8 hours, which means 1,095 settlements a year.
• Fees: 0.10% spot taker and 0.05% perp taker, each paid on entry and again on exit, plus $5 for spread and slippage.
• Maintenance margin: 0.5% of notional.

Income. Each settlement pays $6,500 × 0.0001 = $0.65. Over a year that is $0.65 × 1,095 = $711.75, or 7.1% APR on $10,000 of capital.

Costs. Spot: $6,500 × 0.10% × 2 = $13.00. Perp: $6,500 × 0.05% × 2 = $6.50. Slippage: $5.00. Round trip: $24.50.

Break-even. $24.50 / $0.65 ≈ 38 settlements, or about 13 days at baseline funding. If you exit sooner, you lose money even though funding stayed positive.

Liquidation buffer. With $3,500 of margin behind a $6,500 short and 0.5% maintenance, the short is liquidated after a rise of roughly 53% in BTC. This is approximate because each venue has its own margin tiers. The spot leg gains the same amount, but that gain does not count as margin unless it sits in the same account.

There are two common ways to raise the return on capital:

• Unified or portfolio margin. Some venues let spot holdings count as collateral for the short, after a haircut. You can hold about $9,500 of spot and short the same notional. Because the collateral rises with the price move that hurts the short, the liquidation distance stays large and the return on capital approaches the funding rate on notional. The cost is heavier dependence on one venue's collateral rules, which can change at short notice.
• Higher-funding assets. Altcoin perps often pay more, but they have thinner liquidity, larger swings between cap and floor, and spot legs that are harder to exit. Treat them as a separate risk bucket.

On APR and APY: funding is paid on your current notional and does not compound unless you add the proceeds to the position. Reinvesting at every settlement turns 10.95% APR into about 11.6% APY. In practice you will rebalance weekly or monthly and capture less than that.

Step-by-step execution

1. Pick the asset and venue. Read the contract specification: settlement interval, cap and floor, maintenance margin tiers, your fee tier, and whether spot can count as collateral.
2. Study funding history, not the current print. Look at 7-day and 30-day averages and how often funding went negative. A single high reading says little.
3. Set the capital split. Keep the short leg at about 2x–3x effective leverage or lower, unless you use unified margin with spot as collateral.
4. Enter both legs close together. Buy spot, then short the same coin quantity straight away. Once both have filled, confirm that the quantities match.
5. Set alerts for margin ratio, funding turning negative, and any change to the settlement interval.
6. Rebalance after large moves. After a rally, move profit from spot (or add stablecoins) to the perp account to restore the buffer. After a drop, the short account has excess margin that you can withdraw.
7. Track realized funding every day against your plan. Exit if the running average falls below your break-even plus your required return.
8. Exit both legs together. Close the short and sell spot at the same time. Avoid the minutes around a settlement and avoid volatile spikes.

Risks

Venue failure is the dominant risk. If both legs sit on one exchange, an insolvency, a withdrawal freeze or an account lock takes the whole position with it. The collapse of FTX in 2022 cost hedged traders their collateral even though they had no price exposure. To mitigate this, size positions against what you can afford to lose at a single venue, spread positions across venues, withdraw profits regularly, and consider holding spot in self-custody with the short elsewhere. That last option makes margin harder to manage.

Liquidation turns a hedge into a directional bet. If the short is liquidated in a sharp rally, you are left long spot with no hedge, and you have paid liquidation fees as well. Keep leverage on the short leg low, set alerts, and keep spare stablecoin margin ready to transfer.

Auto-deleveraging can close your short without your consent. In extreme moves, when the insurance fund cannot absorb losses, venues reduce profitable positions on the opposite side. This can partially close your hedge at the worst moment. Watch the venue's auto-deleveraging (ADL) indicator and re-hedge straight away if it triggers.

Funding can turn negative. Short bursts of negative funding are common in sell-offs and usually cost little. Negative funding that persists wears returns down quickly, as the table above shows.

Basis and exit risk. The perp and spot prices are never identical. If you enter when the perp trades at a small premium and exit when the premium is wider, you pay the difference on close, and that can equal several days of funding. Spreads also widen in fast markets. Enter when the premium is modest, exit patiently with limit orders, and structure the position so you are never forced to exit.

Collateral risk. Stablecoin margin carries issuer and depeg risk. Using spot as collateral exposes you to changes in haircuts or eligibility.

When it stops working

Pause the trade or reduce it when any of these apply:

• The 7-day average funding, net of round-trip costs spread over your holding period, is below the yield on a stablecoin strategy with similar risk.
• Funding has been negative for several days in a row and open interest is falling. That is a deleveraging regime, and it can last.
• The venue has moved the contract to hourly settlement because funding is pinned at its cap. This usually signals a crowded, volatile market in which liquidation and ADL risk rise.
• You cannot keep a margin buffer you are comfortable with.

In bear markets the trade usually earns at or below baseline. Treat the strategy as regime-dependent: our 6–20% range covers quiet markets at the low end and sustained leveraged rallies at the high end.

Key takeaways

• Long spot plus short perp, in equal coin size, is approximately delta-neutral and earns funding while funding is positive.
• Put funding rates on the same time basis before annualizing them. 0.01% per 8 hours is 10.95% APR on notional, and less on capital.
• Know your break-even. Entry and exit fees usually take one to three weeks of baseline funding to recover.
• The main risks are venue failure and liquidation of the short leg, not the price of the asset.
• Returns are highest during leveraged bull markets and near baseline or negative in bear markets.