Regular Trading Hours: The perpetual funding rate is calculated from two components:
the premium component (perpetual contract vs. underlying)
added to a base component (fixed at SOFR + 0.5%)
During regular hours, the premium is sampled continuously by comparing the price of the perpetual contract vs. the price of the underlying asset.Outside Regular Trading Hours: The rate snaps to the fixed financing rate (SOFR + 0.5%) and the basis component is dropped:
so positions held overnight or over a weekend don’t face shifting funding.
Corporate actions: these trigger separate automatic adjustments when the oracle reflects the event, keeping the perp aligned with the underlying’s total return.