How to set a trailing stop on Polymarket

What a trailing stop is

A Polymarket price is a probability — a market at 60¢ means roughly a 60% chance of "yes", and each share pays $1 if it resolves your way. An ordinary stop-loss is a fixed level: you set it once and it stays put. A Trail is different — it starts at a level you choose, then ratchets toward the market every time the price moves your way, always keeping the same distance behind. Crucially, it only moves in one direction: when the market goes for you the stop follows it up; when the market pulls back, the stop stays where it climbed to. If the price then reverses all the way to the trailed level, Desk closes the position at market.

The effect is a stop that tightens automatically as profit builds. You never have to keep dragging a fixed stop upward by hand — the Trail does it for you, converting an open gain into a protected one the moment the market extends.

Fixed stop vs Trail

• Fixed stop — one level, set once. It caps your loss but never captures a gain: if the market runs your way and then reverses, the fixed stop is still sitting at its original level, far behind.
• Trail — a moving level, set at a distance. It caps your loss the same way, but as the market extends in your favour the stop trails behind it, locking in an ever-larger slice of the profit.

Use a fixed stop when you simply want a floor; use a Trail when a trade is winning and you want to ride it while it runs but bail the instant it turns.

Arming a Trail in Desk

The Trail lives in the Exits tool, available on both the ladder and the chart, alongside the fixed Stop and the Target take-profit:

1. Open a position, then open the Exits tool.
2. Click Trail to arm it.
3. Click the price on the ladder rung — or the level on the chart — to set the initial stop. The gap between that level and the current price becomes the trailing distance.

From there Desk does the work: as the market moves your way the stop follows behind at that fixed distance; as the market pulls back the stop holds. Reach the trailed level and the position is closed at market.

A worked example

Say you buy "Yes" at 60¢ and arm a Trail 8¢ behind, so the initial stop sits at 52¢.

1. The market runs your way to 80¢. The stop has trailed up with it, staying 8¢ behind — it now sits at 72¢.
2. The price stalls and pulls back. The stop does not move down — it stays at 72¢.
3. The pullback reaches 72¢. Desk closes at market, banking the gain from 60¢ to 72¢ instead of giving it all back.

Had you used a fixed stop at 52¢, that same pullback would have sailed straight past your locked-in profit — the fixed level was never updated. The Trail captured it automatically.

Trailing on a fast, thin market

A Trail closes at market when it's hit, so on a thin or gapping book the fill can land at the next available price beyond the trailed level rather than exactly on it — the Trail bounds your exit, it doesn't guarantee the precise price. Set the distance wide enough that ordinary noise doesn't stop you out early, but tight enough that a real reversal doesn't hand back most of the gain. On liquid markets the slippage is negligible; on a thin, fast one, size accordingly.