The Coincall perpetual contract has no expiration date and traders can hold it indefinitely. The introduction of a funding fee mechanism can anchor the perpetual contract market price to the spot price.
The funding fee is charged every 8 hours at 08:00, 16:00, and 24:00 UTC (actual collection time may vary). Traders will only pay or receive the funding fee if they hold a perpetual contract position at the time of collection. If the position is closed before the fee is collected, no funding fee is required.
Generally, when the market is bullish, the funding fee is positive, and the long position of the perpetual contract pays the funding fee to the short position. When the market is bearish, the funding fee is negative, and the short position of the perpetual contract pays the funding fee to the long position.
Funding Fee Calculation:
Funding Fee = Position Nominal Value * Current Funding Rate
Position Nominal Value = Position Size * Mark Price
Funding Rate Calculation:
The funding rate is affected by the comprehensive interest rate and premium.
Funding Rate = clamp (Average Premium Index + clamp (Comprehensive Interest Rate - Average Premium Index, Premium Deviation Upper Limit, Premium Deviation Lower Limit), Funding Rate Upper Limit, Funding Rate Lower Limit)
- Comprehensive Interest Rate
The daily comprehensive interest rate is 0.03%, and the funding rate settlement frequency is 3 times per day, with each period's comprehensive interest rate being 0.01%.
- Average Premium Index
The average premium index is the arithmetic average of all premium indices in the current period's last 8 hours. For example, the average premium index at 8:30 in the period from 8:00 to 16:00 is the arithmetic average of all premium indices from 8:00 to 8:30.
- Premium Index = [Max (0, Weighted Buy Price - Fair Price) - Max (0, Fair Price - Weighted Sell Price)] / Index Price + Funding Rate Basis
- Weighted Buy Price/Sell Price refers to the average buy/sell order price when the cumulative order amount reaches $8,000, starting from the first order on the buy/sell side.
- Fair Price = Index Price * (1 + Funding Rate Basis). For example, if the current BTC index price is 20,000 and the funding rate basis for the BTC perpetual contract is 0.005%, then the fair price of the BTC perpetual contract is 20,000 * (1 + 0.005%) = $20,001.
- Funding Rate Basis = Last Period Funding Rate * (Time Interval from Current Time to Settlement Time / Settlement Period)
- Premium Deviation Upper Limit: 0.05%; Premium Deviation Lower Limit: -0.05%
- Funding Rate Upper Limit: 0.5%; Funding Rate Lower Limit: -0.5%
For example, if the last period's BTC perpetual contract funding rate was 0.01%, the current time is 12:00, and the settlement time is 16:00, which is 4 hours away, and the settlement period is 8 hours (settled every 8 hours), then the current funding rate basis is 0.01% * (4/8) = 0.005%.
Note that the funding fee will be deducted directly from the available balance in the account and will be deducted up to the maximum available balance. Any excess will not be charged. The platform will also distribute based on the actual deduction, so the amount received by the user may differ from the theoretical calculation. The funding fee history record shows the actual deduction or receipt.