How Funding Rates Work — and Why They Quietly Raise Your Liquidation Risk
Perpetual futures don't expire, so exchanges need a mechanism to keep their price tethered to the spot market. That mechanism is the funding rate — a periodic payment between longs and shorts. It's easy to ignore because it's usually small. On a leveraged position held for days, it isn't.
- Funding is deducted directly from your margin balance every 8 hours on most exchanges — not from your unrealized PnL.
- Holding a leveraged position through funding intervals shrinks your real margin buffer even if price never moves against you.
- Funding rates can spike well above typical levels during trending markets, accelerating this drag.
- Re-check your liquidation price periodically on multi-day holds — the day-one calculation doesn't account for funding paid since.
What a funding rate actually is
A perpetual futures contract has no settlement date, so nothing forces its price back to the spot price the way a dated futures contract's expiry does. Instead, exchanges run a funding mechanism: every funding interval (most exchanges use 8 hours — Binance, Bybit and OKX all default to this), whichever side of the market is "crowded" pays the other side.
- Positive funding rate: longs pay shorts. This happens when the perpetual price trades above spot — more traders are long than short, so long-side pressure is taxed to pull the price back down.
- Negative funding rate: shorts pay longs. The perpetual is trading below spot, so short-side pressure gets taxed to pull the price back up.
The payment is calculated as position value × funding rate, and it's deducted from (or added to) your margin balance directly — not from your PnL calculation, from your actual account margin. That distinction matters more than it sounds like it should.
Why this affects your liquidation price
Liquidation happens when your margin balance falls to the maintenance margin requirement. A liquidation calculator (including ours) shows you the liquidation price at the moment you open the position, based on the margin you allocate then. But if you're paying funding every 8 hours on a leveraged position, your effective margin balance is quietly shrinking even if the price hasn't moved against you at all.
That means your real liquidation price creeps closer to your entry price over time purely from funding drag — a static calculator can't show this because it's a function of how long you hold, not just your entry parameters.
Worked example
You open a $10,000 long position (10x leverage, $1,000 margin) during a period of positive funding at 0.01% per 8-hour interval — a typical rate, though it swings far higher during strong trends.
| Holding period | Funding payments | Cost |
|---|---|---|
| 1 day | 3 | $3.00 |
| 1 week | 21 | $21.00 |
| 1 month | ~90 | ~$90.00 |
$90 against a $1,000 margin allocation is a 9% reduction in your buffer before liquidation — from funding alone, with the price never having moved.
How to actually account for it
- Check the current funding rate before opening a position you plan to hold for more than a few hours — most exchanges display it directly on the trading page, updated continuously.
- Add a funding buffer to your margin, especially on positions you intend to hold through multiple funding intervals — treat it as a known cost, not a surprise.
- Re-check your liquidation price periodically on a multi-day hold, rather than trusting the number calculated on day one — your real buffer has shrunk by whatever funding you've paid since.
- Be aware that being on the "wrong" side of sustained funding compounds — if you're long during a long period of positive funding, that drag doesn't reset; it accumulates every interval until you close.
Our Liquidation Calculator lets you re-run the numbers with your current margin balance at any point — a practical way to approximate funding drag is to simply re-enter your actual current margin (starting margin minus funding paid so far) rather than relying on the day-one calculation.
Conclusion
Funding is a small, recurring cost that most traders only notice once it's already eaten into their margin. It won't liquidate you on its own, but it moves your real liquidation price closer to entry the longer you hold — and that matters most exactly when leverage is already high and buffer is already thin. Check the rate before you enter, and re-check your numbers if you're still holding days later.
FAQ
Sources
- Binance Futures documentation — funding rate mechanics and settlement intervals
- OKX Help Center — funding rate calculation