markets · 5 min

Funding Rates: The Hidden Price of Perpetual Futures

What You Will Learn

  • Why perpetual futures exist and how they stay pegged to spot prices
  • How funding rates work, who pays whom, and what the numbers mean
  • When funding is a hidden cost dragging your returns — and when it’s a systematic edge

The Core Idea

Traditional futures have an expiry date. Perpetual futures don’t. Instead, they use a mechanism called the funding rate to keep the contract price tethered to the spot price. When more traders are long, longs pay shorts. When more are short, shorts pay longs.

This payment happens every eight hours, whether you’re paying attention or not. If you’re trading perpetuals without checking funding, you’re paying a tax you can’t see — and it compounds faster than most traders realize.

Why Perpetuals Exist

In traditional markets, futures contracts expire monthly or quarterly. Traders roll positions from one contract to the next, dealing with basis risk and liquidity shifts on each roll.

Perpetual futures — first introduced by BitMEX in 2016 — eliminated expiry entirely. No rolling, no basis convergence at settlement, no calendar management. Just an open-ended leveraged position on the underlying asset.

The simplicity won. Today, perpetual futures account for the majority of crypto derivatives volume across centralized exchanges and an increasing share on decentralized platforms. They’re the default instrument for leveraged crypto trading.

But removing expiry created a new problem: without a settlement date forcing convergence, what keeps the perpetual price aligned with spot? That’s where funding comes in.

How Funding Rates Work

The funding rate is a periodic payment between long and short holders, calculated based on the difference between the perpetual contract price (mark price) and the spot index price.

When the perpetual trades above spot (mark > index), the funding rate is positive. Longs pay shorts. This incentivizes traders to close longs or open shorts, pushing the perpetual price back toward spot.

When the perpetual trades below spot (mark < index), the funding rate is negative. Shorts pay longs. This incentivizes closing shorts or opening longs, pushing the price back up.

Most exchanges settle funding every 8 hours — typically at 00:00, 08:00, and 16:00 UTC. The rate is usually expressed as a percentage of your position size.

To put the numbers in perspective: a funding rate of 0.01% per 8 hours — often considered the “baseline” — annualizes to roughly 10.95% per year. That’s not trivial. And during strong trends, funding can spike to 0.05%, 0.10%, or higher per interval.

Funding as a Cost: The Invisible Drag

During a strong uptrend, everyone wants to be long. Perpetual prices trade at a premium to spot. Funding goes positive — and stays positive. If you’re holding a long position, you’re paying funding every eight hours for the privilege.

Consider a concrete scenario: you’re long BTC with funding averaging 0.05% per 8-hour interval over one month. That’s three payments per day, 90 payments over 30 days.

0.05% × 90 = 4.5% of your position — gone to funding alone.

If BTC moved up 8% that month, your actual return isn’t 8%. It’s roughly 3.5% before accounting for trading fees and slippage. Many traders look at the price chart, see a profitable move, and never understand why their account tells a different story.

The problem compounds with leverage. At 5x leverage, that 4.5% funding cost becomes 22.5% relative to your margin. Funding can — and does — eat entire positions on leveraged trades held too long during high-funding periods.

Funding as an Edge: Cash-and-Carry

When funding rates are persistently high, they create an opportunity known as the cash-and-carry trade (or basis trade):

  1. Buy the asset on the spot market (long spot)
  2. Open a short perpetual position of equal size (short perp)
  3. Collect funding payments from long holders

Your directional exposure cancels out — you’re market-neutral. Your return comes from the funding payments flowing from longs to your short position.

During periods of extreme bullish sentiment, annualized funding yields have reached 30%, 50%, or more. It looks like free money.

It isn’t.

The risks are real and specific:

  • Liquidation risk. If the price spikes sharply, your short perp can get liquidated before the position rebalances. You need sufficient margin and conservative leverage.
  • Exchange risk. Your spot and your perp may be on the same exchange. If that exchange fails — as FTX demonstrated — you lose both legs.
  • Funding reversal. Sentiment can flip overnight. A position earning +0.10% per interval can suddenly be paying -0.05%. The carry disappears or inverts.
  • Execution costs. Opening and closing both legs involves fees, slippage, and potential timing gaps. The net yield is lower than the raw funding number.

Cash-and-carry is a legitimate strategy, but it requires disciplined risk management — sizing, exchange diversification, and clear exit rules for when conditions change.

Common Failure Modes

  • Ignoring funding entirely — opening a leveraged long during a euphoric market without checking that funding is at 0.10%/8h. The position bleeds out before the trade thesis even plays out.
  • Equating high funding with a short signal — “funding is extreme, it must reverse.” Crowded trades can stay crowded far longer than your margin can survive.
  • Over-leveraging cash-and-carry — using 10x+ leverage on the short leg to maximize yield. One sharp wick and you’re liquidated on the “safe” trade.
  • Ignoring exchange risk — concentrating both legs of a basis trade on a single platform. Diversification across exchanges isn’t optional; it’s the price of participation.