A trailing drawdown is a prop firm loss limit that follows your account's peak as it grows. Each new equity high drags the floor upward, so the room you started with keeps shrinking as you profit - the mechanism that catches more traders than any other rule.
Worked example: $100,000 account, 10% trailing. Floor starts at $90,000. You climb to $105,000 - floor moves to $94,500. You touch $108,000 intraday - floor moves to $97,200, even if you close the day back at $102,000. A $6,000 pullback from that intraday spike, which a static account would shrug off, ends this one.
Two refinements matter. End-of-day trailing only updates the floor at the daily close, so intraday spikes are forgiven. And some futures firms stop trailing once the floor reaches your starting balance - at that point the trailing floor becomes, in effect, a static one at breakeven, which is the friendliest version sold anywhere.
The mechanics in full: trailing drawdown explained; the meaning in plain words: trailing drawdown meaning; the static contrast: static drawdown.
Plain-language material on leveraged-trading risk is maintained by the ESMA investor corner.
Part of the rules & drawdown cluster and the full prop firm glossary.