# Reduce-only orders: closing exposure without reversing it

Reduce-only restricts an order to decreasing an existing position rather than increasing exposure or reversing its direction. It is useful when several closing instructions coexist, but the exact rejection, resizing and time-in-force rules are implementation-specific. The retrieved dYdX guide requires IOC for reduce-only orders.

Evidence: [Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order)

Canonical: https://degreesofsatoshi.com/encyclopedia/reduce-only-orders/
Published: 2026-10-02
Substantively modified: 2026-10-02
Independently verified by an automated reviewer: 2026-10-02T19:18:00.092Z
Data current through: 2026-10-02

AI-assisted research and drafting with a separate automated source-verification pass; no external expert or named human review is implied.

## Key facts

- **Exposure:** A reduce-only order cannot enlarge or flip the position under the documented rule. ([Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order))
- **Policy:** The cited dYdX guide supports reduce-only with IOC. ([Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order))
- **Conditional orders:** Documented stop/take-profit orders can resize to remaining position size when triggered. ([Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order))

## Protect against an outdated close size

Suppose a trader is long 4 A of contract exposure and places two separate sell instructions. If the first closes 3 A, only 1 A remains long. An unrestricted later sell of 4 A could close that unit and establish a 3 A short. A reduce-only constraint prevents that reversal.

This describes exposure, not ownership of spot tokens.

Evidence: [Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order)

## Rejection and resizing are different outcomes

The dYdX guide distinguishes oversized market/limit orders, which can be rejected, from reduce-only stop or take-profit orders that resize at triggering. Do not assume every platform silently trims every oversized order.

The flag also does not create liquidity or remove price constraints. A valid reducing order can be partially filled or unfilled.

Evidence: [Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order)

## Check what remains after execution

After a fill, inspect the actual position and any other live closing orders. A button labelled Close may apply useful defaults, but a separately submitted market order need not inherit them. The transaction record and position state are the evidence that exposure changed.

Evidence: [Interface of the Trade tab](https://help.dydx.trade/en/articles/166979-interface-of-the-trade-tab); [Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order)

## Questions

### Can reduce-only open my first short position?

No. With no long position to reduce, a sell that establishes a short contradicts the constraint.

Evidence: [Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order)

## Claims and scope

### reduce-only-orders-quick-answer

Reduce-only restricts an order to decreasing an existing position rather than increasing exposure or reversing its direction. It is useful when several closing instructions coexist, but the exact rejection, resizing and time-in-force rules are implementation-specific. The retrieved dYdX guide requires IOC for reduce-only orders.

Scope: {"collection":"defi","dataAsOf":"2026-10-02","blockHeight":null}

### reduce-only-orders-fact-exposure

Exposure: A reduce-only order cannot enlarge or flip the position under the documented rule.

Scope: {"collection":"defi","dataAsOf":"2026-10-02","blockHeight":null}

### reduce-only-orders-fact-policy

Policy: The cited dYdX guide supports reduce-only with IOC.

Scope: {"collection":"defi","dataAsOf":"2026-10-02","blockHeight":null}

### reduce-only-orders-fact-conditional-orders

Conditional orders: Documented stop/take-profit orders can resize to remaining position size when triggered.

Scope: {"collection":"defi","dataAsOf":"2026-10-02","blockHeight":null}

## Sources

- [Reduce Only Order](https://help.dydx.trade/en/articles/166978-reduce-only-order) — dYdX Operations Services. Version-scoped IOC requirement and reduction behavior. Locator: Requirements; How it works. Retrieved: 2026-10-02T18:53:20.744Z.
- [Interface of the Trade tab](https://help.dydx.trade/en/articles/166979-interface-of-the-trade-tab) — dYdX Operations Services. Definition and presentation of trading market metrics. Locator: Orderbook; Position information; Stats. Retrieved: 2026-10-02T18:53:20.712Z.

## Revision history

- 2026-10-02: First publication after primary-source research and separate automated verification.

## Cite this entry

Degrees of Satoshi editorial project. “Reduce-only orders: closing exposure without reversing it.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/reduce-only-orders/