Why TWS paper fills differ from live trading

Quick answer

Paper trading is a simulation. It is useful for checking setup and order handling, but its fills can differ from live execution. Compare contract, data, and order settings without treating a paper result as a live-fill promise.

Educational software guidance. Trading involves risk. Read the financial and information disclaimers.

Step by step

1 Confirm the paper and live comparisons use the same contract and order attributes.
2 Check whether each session receives the same data type.
3 Read IBKR’s paper-trading limitations for the order type involved.
4 Use paper results to check message flow, account routing, and basic order behavior.
5 Record execution differences separately from setup failures.
The Trades tab in the paper session records each execution with its time, instrument and action, so differences can be noted separately.

A practical example

A paper limit fills quickly, while a similar live order waits. That does not by itself show that the live setup is broken. Paper trading models fills; live trading depends on the real order book and route. Use paper to check which account, symbol, size, and exit orders the app sends. Keep a separate note for what the test did not prove, such as the price or speed of a future live fill.

Illustrative scenario, not a record of a trade placed during this review.

Screen reference

Empty TWS Activity Orders panel and Trades tab — Use Orders to inspect order state and Trades to inspect executions. This empty paper view shows the location; it does not reproduce a rejection or prove a fill. Captured in TWS paper mode on 3 October 2026. Open the image for full size.

How to confirm the result Your test notes should state what the paper test proved and what still depends on live markets.

Mistake to avoid

Do not publish paper fills as evidence of guaranteed speed, slippage, or profitability in a live account.

Common questions

Can paper test whether an alert reaches TWS?

Yes, with broker-side evidence of the intended paper order.

Does a paper stop fill prove a live exit price?

No. Live liquidity, routing, and market movement remain needed.

TWS says Submitted but the order has not filled TWS order stuck on PendingSubmit TWS order is Inactive: find the actual reason A paper test for TradingView to IBKR automation

Financial and information disclaimers

Financial disclaimer

These guides explain software. They are for education, not financial, investment, tax, or legal advice. No example is a suggestion to buy or sell a product or use a trading strategy. Trading can lose money, including all funds you put at risk. With margin, futures, short sales, or some options, losses can exceed your starting funds. Automation can fail, send duplicate orders, or act late. Stops do not guarantee a fill or a price. Review your orders and positions, and seek advice from a qualified professional for your own needs. Paper trades, examples, and past results do not predict live results or promise a profit.

Information disclaimer

This is general help based on the sources and check date shown on the page. Screens, settings, fees, data access, and product support can change or differ by app version, account, country, and broker. The content may contain errors or become out of date; accuracy, completeness, and continuous service are not guaranteed. Check current broker and app instructions before acting. Screenshots show where controls are; they do not prove that an order test passed. This guide does not replace broker terms or risk notices. References to IBKR and TradingView identify their products and do not imply their endorsement of this guide.