Scaled order: quantity distributed across prices

A scaled order divides an intended total quantity into component orders with defined prices and quantities. It is an execution structure, not a universal entry method, and it does not assure a better average price.

How it is constructed

Each component is often a limit order: a buy may execute at the limit price or lower and a sell at the limit price or higher. It may remain unfilled even if the market approaches its level; it may also receive a partial fill, meaning that only part of its quantity executes.

The minimum structure contains a side — buy or sell —, total quantity, starting price, price increment, and component quantity. The component quantities should add up to the intended total, apart from rounding required by minimum tradable quantity and price-increment rules.

The label does not identify one technology. A trader may submit several orders at once; a platform may treat them as a group; an algorithm may instead release the next component only after the preceding one fills. Interactive Brokers' ScaleTrader, for example, follows the latter sequence. The broker's actual logic must therefore be checked rather than inferred from the word “scaled.”

Quantities, prices, and actual average

Equal quantities at every level are often called a uniform scale. With different quantities, the scale is weighted: increasing size at lower prices shifts the average if those levels fill, but it also concentrates capital and risk where the market has moved against the initial entry. This is not a recommendation to increase a position.

Average price must be calculated from fills: add each “executed quantity × executed price,” then divide by total executed quantity. Fees and other costs must be recorded separately or included in total cost, without using theoretical prices from orders that remain open.

Verification sequence and risks

This page describes a structure; the choice of levels, weights, and side remains a separate operating decision.

1. Check total quantity, component sum, minimum price increment, minimum tradable quantity, and reserved funds or margin.
2. Establish whether orders are simultaneous or sequential and which event releases the next component.
3. Define duration, cancellation rule, and partial-fill handling before submission.
4. Recalculate position size, average price, and risk after every fill.

An unfilled limit can leave the position smaller than planned; a fully executed sequence can instead concentrate maximum exposure during an adverse move. More components create more states to monitor and may multiply fees. Any protective exit is a separate order with its own triggering and execution conditions.

Technical depth: weights, queue, and order state

The weight progression may be constant, increasing, decreasing, or manually specified. An increasing progression does not “optimize” price by definition: it changes the exposure distribution and gives the last level more influence. Queue priority, available liquidity, and partial fills can also make the actual scale diverge from its design.

Sources

• Interactive Brokers — Order Types and Algos: ScaleTrader — describes automated division of an order into incrementally priced and sized limit components.
• Interactive Brokers — Example 1: Basic Scale Orders — shows sequential release of components after the previous level fills.
• SEC — Limit Orders — explains the price constraint and absence of an execution guarantee.
• FINRA — Time Parameters and Qualifiers on Stock Orders — documents duration, fill-or-kill, immediate-or-cancel, and partial fills.

Links

• limit-order — maximum buy price or minimum sell price.
• trade-size — position quantity.
• risk-per-trade — exposure planned before execution.
• slippage — difference between expected and executed price.
• grid-trading — orders at levels with automatic buy-and-sell cycles.