API Update: Introducing the 'pool' field to the order, execution, orderBookL2, orderBook10, quote, quoteBin, trade, tradeBin end points

At BitMEX, we are committed to continually improving our platform and its infrastructure to support advanced trading capabilities for our users. As part of this ongoing effort, we are announcing an update to our REST and WebSocket APIs.

From 3 February 2025, a new field, pool, will be added to the following BitMEX REST and WebSocket API responses. The field will be empty initially and populated with string value in future releases.

REST GET end points:

• /api/v1/order

• /api/v1/execution

• /api/v1/quote

• /api/v1/quote/bucketed?binSize=1m

• /api/v1/quote/bucketed?binSize=5m

• /api/v1/quote/bucketed?binSize=1h

• /api/v1/quote/bucketed?binSize=1d

• /api/v1/trade

• /api/v1/trade/bucketed?binSize=1m

• /api/v1/trade/bucketed?binSize=5m

• /api/v1/trade/bucketed?binSize=1h

• /api/v1/trade/bucketed?binSize=1d

WebSocket feeds:

• orderBookL2

• orderBookL2_25

• orderBookL2_100

• orderBook10

• quote

• quoteBin1m

• quoteBin5m

• quoteBin1h

• quoteBin1d

• trade

• tradeBin1m

• tradeBin5m

• tradeBin1h

• tradeBin1d

Effective Date and Time: 3 February 2026, 06:00 - 09:00 UTC

This will be available in BitMEX Testnet from 28 Jan 2026 from 06:00 - 09:00 UTC.

What is Changing?

A new field, ^pool, will be added to the response of the REST and WebSocket API listed above.

Please refer to a snippet example in the REST and WebSocket API below:

^{/api/v1/order?symbol=XBTUSD}

^{"account":1234567,}

^{"orderID":"81000000-0000-0000-0000-000000000000",}

^{"pool": "Primary"}

^{"symbol":"XBTUSDT",}

^{"maxSlippagePct":"40.0",}

^{/api/v1/execution?symbol=XBTUSD}

^{"account":1234567,}

^{"execID":"2e8f42c4-1b86-291b-c371-87a2c503b1a8",}

^{"pool": "Primary"}

^{"symbol":"XBTUSDT",}

^{"maxSlippagePct":"40.0",}

^{"execType": "Trade",}

Why are we making this change?

The addition of the pool field is necessary to facilitate protected order books to maintain tighter spreads with much larger liquidity for a subset of traders. This feature is work in progress and will be released in phases.

This is an additive change, meaning it introduces a new field without removing any existing data. Most integrations should be unaffected.

If you have any questions about these upcoming changes, please contact Support.

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