# ib_async The community continuation of ib_insync — same API, new maintainers, TWS still required. *https://stockmarketstack.com/tools/ib-async · Backtesting Frameworks & Algo Trading Libraries* ## Facts ### At a glance | Field | Value | | --- | --- | | Vendor | ib-api-reloaded | | Category | Backtesting Frameworks & Algo Trading Libraries | | Job | live_trading | | Website | https://github.com/ib-api-reloaded/ib_async | | Pricing model | open-source | | Free tier | true | | Open source | true | | Licence | BSD-2-Clause | | Self-hosted | true | | Tested hands-on | false | | Last updated | 2026-09-14 | ### Coverage | Field | Value | | --- | --- | | Asset classes | stocks, etf, options, futures, forex, crypto, bonds, indices, mutual_funds, commodities | | Markets | global | | Works outside the US | true | | Data latency | none | | Platforms | library | | AI features | none | ### Interfaces | Field | Value | | --- | --- | | API | false | | Webhooks | false | | Scripting | Python | | Python | true | | Spreadsheet add-in | false | | MCP server | false | | Export | none | ### Capabilities Yes: scanning, automation, live_trading, paper_trading, portfolio_tracking, broker_import, news, options_analysis No: charting, screening, backtesting, tax_reporting, alerts *Verified: pricing 2026-09-14; capabilities 2026-09-14; coverage 2026-09-14.* ## What it is ib_async is a Python library that speaks Interactive Brokers' TWS API protocol directly and hands back typed objects — `Stock('AAPL', 'SMART', 'USD')`, `ib.reqHistoricalData(...)`, `ib.placeOrder(...)`. The design is ib_insync's, unchanged: a linear synchronous style that works in scripts and Jupyter, the same calls available as `...Async` coroutines for asyncio applications, and an `IB` object that keeps positions, orders and account values in sync as events arrive from the gateway. It is a continuation, and the dates are worth stating precisely. ib_insync's author, Ewald de Wit, died on Monday 11 March 2024. The notice is in that repository's own README, signed by Maritza and Philippe de Wit, added by a commit titled "In memoriam" on 14 March 2024 — the last commit it ever received, and the repository is now a public archive. Five days after it, on 19 March 2024, ib_async 1.0.0 was published to PyPI under a new GitHub organisation, `ib-api-reloaded`, which describes itself as an "Alternative Interactive Brokers API Client (unaffiliated)". The LICENSE file carries both copyright lines — Ewald de Wit for 2019–2023, Matt Stancliff for 2024 — under unchanged BSD 2-Clause terms. Its current state, also by date: version 2.1.0 went to PyPI on 8 December 2025, and the default branch `main` last moved two days before that. Work did not stop — the `next` branch carries commits through 14 July 2026 — but none of it is released, and there is no `v2.1.0` tag or GitHub release at all. The newest release on the repo is v2.0.1 from 22 June 2025. Install from PyPI today and you get December's code. ## Pricing Nothing is for sale — no pro build, no hosted tier, no commercial licence. The bills belong to Interactive Brokers: an IBKR account with API access, plus a market-data subscription for any real-time quote the library streams. Delayed quotes need no subscription and are one call away with `ib.reqMarketDataType(3)`. ## Data & coverage Whatever the account behind the gateway can see. The contract classes are `Stock`, `Option`, `Future`, `ContFuture`, `Forex`, `Index`, `CFD`, `Commodity`, `Bond`, `FuturesOption`, `MutualFund`, `Warrant`, `Crypto` and `Bag` combos — IB's instrument range rather than a curated one. Past quotes and historical bars, the client exposes IB's scanner (`reqScannerData`), market depth, historical ticks, fundamental data, news providers and historical news, Wall Street Horizon event data, `calculateImpliedVolatility` and `calculateOptionPrice`, account summary, positions and PnL streams. None of it is ib_async's data, and entitlements stay IB's question. ## Integrations `pip install ib_async`, and the name is the project's own: PyPI lists the repository as `ib-api-reloaded/ib_async` with Matt Stancliff as maintainer, and the README prints that same line. The trap is next door — `ib_insync` is still installable, resolving to 0.9.86 from July 2023 and pointing at the archived repo. Nothing warns you. Python 3.10 or newer and three dependencies: `aeventkit` (the organisation's fork of de Wit's eventkit, renamed on PyPI, still imported as `eventkit`), `nest_asyncio` and `tzdata`. What it connects to is a desktop application — TWS with API mode enabled, default port 7497, or IB Gateway on 4001, with "Download open orders on connection" checked. `ib_async.ibcontroller` ships `IBC` and `Watchdog` to launch that app with `tradingMode` set to `live` or `paper` and restart it when it dies — the part everyone needs by week two. `FlexReport` pulls IB Flex statements by token and query id for the account history the live API will not give you. ## Limitations - **Useless without an IB account.** Not a licensing restriction — the code is free to read, fork and run — but it connects to nothing unless TWS or Gateway is running and logged in. - **Not a REST client.** IB's Web API is a different product; this speaks the socket protocol to a Java desktop app that has to stay up through IB's daily restarts. - **The protocol range is pinned in the source.** `MinClientVersion` is 157 and `MaxClientVersion` 178, so the handshake advertises `v157..178` and anything older is dropped with "TWS/gateway version must be >= 972". Fields IB adds above 178 arrive when a maintainer raises the ceiling. - **The client throttles itself** to `MaxRequests = 45` per second, and IB's own pacing rules sit behind that — historical-data requests in particular. - **Nine months since the last release**, with the active work sitting unreleased on `next`. - **Effectively one maintainer.** The organisation shows no public members, and commits on both branches are overwhelmingly from one account. - **No backtester.** This is a connection, not a research stack. - **Unaffiliated with Interactive Brokers.** When the API changes, you have an issue tracker. ## Alternatives If what you want is the engine rather than the connection, [NautilusTrader](https://stockmarketstack.com/tools/nautilus-trader) reaches IB through its own adapter and gives you a backtester that runs the same strategy live, and [QuantRocket](https://stockmarketstack.com/tools/quantrocket) wires Zipline and Moonshot to IB inside Docker. [backtrader](https://stockmarketstack.com/tools/backtrader) has an IB store too, but it rests on IbPy, archived since January 2017. The rest of the shelf is in [backtesting frameworks](https://stockmarketstack.com/categories/backtesting-frameworks). ## FAQ ### Is ib_async the same project as ib_insync? It is its continuation, not a rename. ib_insync's author, Ewald de Wit, died in March 2024; the archived repository's last commit added a notice from his family. ib_async 1.0.0 was published five days later by a new GitHub organisation, keeping the code, the BSD 2-Clause licence and his copyright line. ### Can I still use ib_insync? It still installs — 0.9.86, uploaded in July 2023 — and it still works against TWS. Nothing will be fixed in it, because the repository is a public archive. Anything new, including support for newer protocol fields, happens in ib_async. ### Do I need an Interactive Brokers account to use ib_async? Yes. The library is free to read and run, but it connects to a locally running TWS or IB Gateway logged into an IBKR account. Without those credentials it has nothing to talk to, and real-time quotes additionally need market-data subscriptions bought from IB. ### Does ib_async need IB's own ibapi package? No. It implements the TWS API binary protocol itself, and its only runtime dependencies are aeventkit, nest_asyncio and tzdata. pandas is optional and is imported only by the util.df and util.barplot helpers. ## Also worth comparing - [Lumibot](https://stockmarketstack.com/tools/lumibot.md) — One strategy class for backtest and live, plus a built-in LLM agent runtime. - [NautilusTrader](https://stockmarketstack.com/tools/nautilus-trader.md) — Rust core, Python API, one strategy that backtests and trades live unchanged. - [StockSharp](https://stockmarketstack.com/tools/stocksharp.md) — C#/.NET algo stack with 384 connectors; source is published but no longer open source. - [Backtesting.py](https://stockmarketstack.com/tools/backtesting-py.md) — A single-instrument Python backtester — one OHLC series, one strategy, no live trading. - [Backtrader](https://stockmarketstack.com/tools/backtrader.md) — An event-driven Python backtester with 122 indicators, frozen since April 2023. - [bt](https://stockmarketstack.com/tools/bt.md) — Python backtesting for allocation and rebalancing rules, not entries and exits.