Copy trading costs: a clear definition
Copy trading costs are the real charges and cost effects that occur when one account (“the signal/copy provider’s account”) is copied into another account (“the follower’s copied account”). In practice, costs usually come from more than one layer:
- Platform or copying service charges: fees or markups charged specifically for using copy features.
- Execution and broker-related costs: items linked to trading mechanics such as spreads, commissions, and financing-related charges (if trades are held).
- Copying mechanics effects: differences caused by how orders are mapped and executed (for example, partial fills or execution timing).
This article gives a worked example of the calculation approach using simple assumptions. It does not use live prices or any specific provider’s current fee schedule.
How a worked example works (mechanics and inputs)
A worked example needs explicit assumptions. Here is a minimal set of inputs you can reuse:
- Trade size mapping rule: how the follower’s copied position size relates to the provider’s position size.
- Entry and exit costs model: whether you model costs as (a) spread only, (b) commission only, or (c) both.
- Timing and execution assumptions: whether you assume the copy executes at the same price and quantity as the provider, or whether you allow for differences.
- Holding period assumptions: whether you include any financing/overnight charges due to holding positions.
To separate stable mechanics from variable conditions:
- Treat the fee schedule and commission/spread assumptions as inputs.
- Treat market outcomes (price movement, spread changes) as variables that change in real time.
Worked numerical scenario: all assumptions stated
Below is a single, simplified round-trip scenario (open and close one position). You can treat the numbers as placeholders to understand the cost flow.
Assumptions
- Provider opens a trade and closes it once later.
- Follower copies 1:1 lot size (the follower opens the same lot size as the provider).
- Commission: the broker charges $3.00 per lot per side (per open and per close).
- Spread effect: you model the spread as 0.00020 in price terms. To convert to money, assume a $10.00 per pip per lot conversion.
- Price move (mid-price): from entry to exit, the mid-price moves 20 pips in favor of the position.
- No overnight/financing charges (holding time short enough to ignore financing).
- No slippage and no partial fills: the copied execution matches the provider mapping exactly.
- Copy-platform fee model: assume a one-time $2.00 platform fee per copied trade, regardless of result.
Step 1: Commission cost
Commission is paid on both entry and exit:
- Entry commission: $3.00 per lot
- Exit commission: $3.00 per lot
- Total commission = $6.00
Step 2: Spread cost
If the spread is 0.00020 and you map it to 2 pips (because pip size depends on instrument; here we assume 0.00020 corresponds to 2 pips for this example), then spread reduces net performance.
- Total spread cost = 2 pips × $10.00 = $20.00
(This is a simplified conversion. In reality, pip value depends on the instrument, account currency, and position size rules.)
Step 3: Trading “gross” profit from the price move
- Mid-price move: +20 pips
- Value: 20 pips × $10.00 = +$200.00
Step 4: Apply platform fee
- Platform fee = $2.00
Step 5: Compute net result
Net = Gross move − spread − commission − platform fee
- Net = $200.00 − $20.00 − $6.00 − $2.00
- Net = $172.00
What changes in a losing scenario?
If the mid-price move were −20 pips instead, then:
- Gross = −$200.00
- Net = −$200.00 − $20.00 − $6.00 − $2.00 = −$228.00
The key point: costs are often paid regardless of direction, and spread can effectively “consume” part of the move.
Material limitations and failure modes
Even with a correct arithmetic example, real outcomes can differ because the inputs are rarely constant.
- Spread and commission change by moment: spreads widen during volatility, and some fee schedules can vary by account type. 2. Execution differences (slippage/partial fills): copying may not fill at the same prices or quantities, changing both gross profit and effective cost. 3. Lot-size mapping is rarely perfectly identical: some systems scale by equity, risk constraints, minimum lot sizes, or margin limits, which breaks the “1:1” assumption. 4.