How is a simulated fill different from a real fill?

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Accepted Answer

A real fill comes from a market or liquidity provider and depends on available volume, so large orders can move price or partially fill. A simulated fill is calculated by software from the current quoted price, usually at the bid or ask. Good simulators use live prices and real spreads so results stay realistic.
What differs:
Liquidity: real fills depend on order book depth; simulated fills usually assume the quoted price is available.
Slippage: real orders can slip in fast markets; simulators may or may not model it.
Latency: real orders travel to a venue; simulated fills happen internally.
Partial fills: possible in real markets, rare in simulators.
For a prop firm, the goal is realism without unfairness: traders should see the prices they would get in the market. PropExecutor fills market orders at the live bid or ask from the feed, with raw spreads, and triggers pending orders, stop losses and take profits from the same live prices.
### Explaining it to traders
A short section on your rules page covering fill prices, stops and gaps prevents most execution disputes.
### What realism means for payouts
The closer simulated fills are to real ones, the more a funded trader's results mean, which matters for any firm that later copies traders into real markets.

How is a simulated fill different from a real fill?

Detailed answer

Explaining it to traders

What realism means for payouts

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