Compare spot and futures on the same executed notional. For linear USDT contracts, trading fees use position notional, not posted margin; perpetual funding is a separate cost.
What changes the answer
A spot fee can be charged in the acquired asset. Linear USDT futures fees are calculated from filled notional. Inverse contracts and options have their own formulas, so do not apply a linear-contract example to every derivatives product. Use a consistent USDT valuation for comparisons.
For illustration, 10,000 USDT at a hypothetical 0.10% spot rate costs 10 USDT for one fill. The same notional at a hypothetical 0.06% linear-futures rate costs 6 USDT. A 1,000 USDT margin does not turn the 10,000 USDT notional into a 1,000 USDT fee base. Neither rate is a current exchange quote.
Opening and closing are separate fills. If both sides each execute for 10,000 USDT at 0.06%, total trading fees are 12 USDT; if your monthly executed volume already includes both, do not double it again. Add any applicable funding separately. Funding can be paid or received and is not fee cashback.
Calculate the cost on the same basis
Compare the same product, pair, country, VIP tier and execution assumptions. Trading volume counts executed buys and sells; do not double it again if both sides are already included. Fee cashback covers approved eligible trading fees, not funding, spread, slippage, liquidation, borrowing or withdrawal costs. An estimate is not a payment or a guarantee of eligibility.
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