Upcoming Upgrade to Our Margining System and API

Postmortem Announcement

We are upgrading our trading technology to improve the speed and stability of our exchange. As an initial step, we have already started moving pilot users’ accounts to the upgraded system.

BitMEX will gradually move all users’ trading accounts to the new system from 25 March 2024 onwards. We expect this process to take approximately 3 weeks, and we will make an announcement once completed. 

Users will not need to take any action to be migrated, but they should be aware of these important changes to the API and cross margining system as a result of this upgrade.

For our API users, we encourage you to test any trading software in our Testnet environment. All accounts on testnet.bitmex.com have already been migrated to the new system.

Please contact your Relationship Manager or our 24/7 Support if you have any questions. 


API Changes

The new system can process more than one order at a time, which requires the introduction of pending order states similar to those in the FIX protocol. This means BitMEX may send an Order status update via REST or Websocket API with one of the following values in its OrderStatus:

  • PendingNew
  • PendingReplace
  • PendingCancel

These states are not normally exposed. However, they might be sent out in some scenarios. For example, if a cancellation in progress has not yet been confirmed and another cancellation for the same order comes in, then the order status would be PendingCancel and the execType CancelReject. 

Traders may need to update their trading software to handle these pending order states. 


Changes to Cross Margining System

We have further made updates to how our Cross Margining system works, helping to improve capital efficiency (and allow users to trade more):

  • Unrealised PnL can now be shared between positions in cross margin.
  • Under cross margin, only the maintenance margin is locked.
  • Under cross margin, all cross margin positions for an account would be liquidated at the same time.
  • While unrealised PnL can be used as margin for derivatives positions, only realised balances can be withdrawn, transferred, or used to trade Spot or Convert.

Due to these changes, users may notice changes in their position table and/or position display lines on charts when using our web or mobile interface. 

The experience for positions using Isolated Margin will be identical to the existing BitMEX experience.

As we progress with the system upgrade, please stay tuned for an upcoming blog post where the changes will be discussed in more detail. In the meantime, if you have any questions, please contact Support who are available 24/7. 


To be the first to know about our new listings, product launches, giveaways and more, we invite you to join one of our online communities and connect with other traders. You can also follow us on Twitter, or read our blog and site announcements for the absolute latest.