Interactive Brokers API Order Placement and Fill Reconciliation
Summary
This technical guide explains how a Python client for Interactive Brokers can resolve futures contract details, submit market and limit orders, and modify or cancel open orders. It describes tracking order identifiers and listening for broker callbacks, including checking that cancellation is confirmed rather than assuming a request succeeded.
A major focus is capturing executions and commissions. The guide distinguishes live fill events from requested execution history, collects callback data through queues, joins commission records to executions, and removes duplicates. It also explains why a trading system should reconcile its own trade database against broker records: fills may be missed if the client is offline or fails before recording them. The author notes that broker execution history is available only through the current day in this workflow, so older missing fills require manual lookup. The material is an implementation-oriented API walkthrough; it demonstrates plumbing and operational practices rather than a trading strategy or evidence of profitability.
Key ideas
- Resolve the broker's contract details before submitting an order.
- Track order identifiers and confirm broker callbacks for order updates and cancellations.
- Combine execution records with commission reports to calculate trading costs accurately.
- Reconcile local trade history against broker records because a client can miss fill events.
- In this workflow, execution history is limited to the current trading day, so older gaps may need manual repair.
Tags
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.