How to estimate the cost of an automated strategy.

Start with executed notional

If an illustrative order is worth $200 and its applicable fee is 0.05%, multiply 200 by 0.0005. The charge is $0.10 for that fill. Another fill is another charge. This is arithmetic using an assumed rate, not a statement about every product or account.

Order cancellation and order execution are different events. For the actual charges relevant to your strategy, inspect the official schedule and account records rather than relying on a generic example.

Turnover compounds the cost burden

An invented set of 100 fills, each worth $200 at that same assumed rate, has $20,000 of executed notional and $10 of trading charges. It does not require a $20,000 deposit because the same capital may be traded repeatedly.

This example says nothing about profits. It isolates one cost. Price changes, the inventory held at the end and other expenses determine whether the complete strategy gains or loses money.

Include costs outside the fee line

Spread and slippage can reduce the value of a completed trade even when the published fee looks small. Futures can introduce funding payments. Withdrawals or conversions can add separate charges. The relevant total depends on the actual execution and funding route.

Do not treat a displayed fee as a guarantee of an all-in execution price. Liquidity changes, and a price quoted before submission may differ from what an order receives.

Compare consistent outcomes

A useful comparison uses the same starting allocation and period, accounts for later deposits and withdrawals, and values all remaining inventory. Compare net outcomes rather than a count of successful trades.

A strategy can have many small realized gains and one large remaining loss. Keeping open inventory outside the calculation makes the report easier to admire and less useful for a decision.

Make an execution-cost worksheet

• Record each executed order’s notional and actual fee.
• Separate trading charges from funding, conversions and withdrawals.
• Document assumptions for spread and slippage; replace them with actual execution data when available.
• Include open inventory in the final valuation.
• Check current official rates before each new strategy decision.