> ## Documentation Index > Fetch the complete documentation index at: https://docs.kalshi.com/llms.txt > Use this file to discover all available pages before exploring further. # Connectivity > Endpoints, transport configuration, and rate limits for the Kalshi FIX API ## Endpoints **Production** **Order Entry Host:** `mm.fix.elections.kalshi.com` **Market Data Host:** `marketdata.fix.elections.kalshi.com` | Purpose | Port | TargetCompID | Description | | - | - | - | - | | Order Entry (without retransmission) | 8228 | KalshiNR | Submit, modify, and cancel orders; no message persistence or retransmission. Supports [Listener Sessions](/fix/listener-sessions) for read-only streaming | | Order Entry (with retransmission) | 8230 | KalshiRT | Order entry with message retransmission, RFQ creation, and optional settlement reports. Supports [Listener Sessions](/fix/listener-sessions) for read-only streaming. Contact [institutional@kalshi.com](mailto:institutional@kalshi.com) for access | | Drop Copy | 8229 | KalshiDC | Request-response queries for historical execution reports; [gated access](/fix/drop-copy), contact [institutional@kalshi.com](mailto:institutional@kalshi.com) | | Post Trade | 8231 | KalshiPT | Read-only stream for market settlement reports and position resolution. Contact [institutional@kalshi.com](mailto:institutional@kalshi.com) for access | | RFQ | 8232 | KalshiRFQ | Market maker session for receiving RFQ broadcasts, submitting quotes, and managing quote lifecycle | | Market Data | 8233 | KalshiMD | Order book snapshots and incremental updates. Available only on market data host | **Demo** **Order Entry Host:** `fix.demo.kalshi.co` **Market Data Host:** `marketdata.fix.demo.kalshi.co` | Purpose | Port | TargetCompID | Description | | - | - | - | - | | Order Entry (without retransmission) | 8228 | KalshiNR | Submit, modify, and cancel orders; no message persistence or retransmission. Supports [Listener Sessions](/fix/listener-sessions) for read-only streaming | | Order Entry (with retransmission) | 8230 | KalshiRT | Order entry with message retransmission, RFQ creation, and optional settlement reports. Supports [Listener Sessions](/fix/listener-sessions) for read-only streaming. Contact [institutional@kalshi.com](mailto:institutional@kalshi.com) for access | | Drop Copy | 8229 | KalshiDC | Request-response queries for historical execution reports; [gated access](/fix/drop-copy), contact [institutional@kalshi.com](mailto:institutional@kalshi.com) | | Post Trade | 8231 | KalshiPT | Read-only stream for market settlement reports and position resolution. Contact [institutional@kalshi.com](mailto:institutional@kalshi.com) for access | | RFQ | 8232 | KalshiRFQ | Market maker session for receiving RFQ broadcasts, submitting quotes, and managing quote lifecycle | | Market Data | 8233 | KalshiMD | Order book snapshots and incremental updates. Available only on market data host | Historical replay through `EventResendRequest` (`35=U1`) on both `KalshiNR` and `KalshiDC` requires [account allowlisting](/fix/drop-copy). NR users can log in and trade without replay access. ## Session Configuration All connections use **FIXT.1.1** with application version **FIX50SP2**. | Parameter | Value | | - | - | | SenderCompID | Your FIX API Key (UUID format) | | TargetCompID | See endpoints table above | | Session ID | `TargetCompID + SenderCompID` | Only one FIX connection is allowed per API key. Separate API keys are required for concurrent connections. ## SSL/TLS You must use TLS 1.2 or higher (not plain TCP) to connect to the FIX gateway. Cipher suites follow [AWS Network Load Balancer TLS policies](https://docs.aws.amazon.com/elasticloadbalancing/latest/network/create-tls-listener.html#describe-ssl-policies). If your FIX implementation does not support native TLS connections, use a local proxy such as [stunnel](https://www.stunnel.org/). To obtain the server certificate for pinning on the initiator side: ```bash theme={null} openssl s_client -showcerts -connect : < /dev/null | openssl x509 > kalshi-fix.pem ``` For example, to pin against the demo order entry endpoint: ```bash theme={null} openssl s_client -showcerts -connect fix.demo.kalshi.co:8228 < /dev/null | openssl x509 > kalshi-fix.pem ``` ## Private Connectivity For participants requiring network-level isolation, Kalshi supports private connectivity via [AWS PrivateLink](https://docs.aws.amazon.com/vpc/latest/privatelink/what-is-privatelink.html). With PrivateLink, FIX traffic is routed entirely within the AWS backbone and never traverses the public internet. Members on the Premier tier or above can contact [institutional@kalshi.com](mailto:institutional@kalshi.com) to provision a PrivateLink endpoint for their AWS account. Members on the Prime tier or above can also contact [institutional@kalshi.com](mailto:institutional@kalshi.com) to discuss VPC peering for production connectivity from their AWS VPC. ## Rate Limits * **Limit**: FIX application messages use the same token model, token costs, and Read/Write buckets as the equivalent REST API operations. * **Scope**: Application messages only (from client to server) * **Excluded**: Logout (35=5), Heartbeat (35=0), TestRequest (35=1) * Logon (35=A) is rate-limited separately from application messages. See [Reconnecting](/fix/authentication#reconnecting) for retry guidance. * Order-entry and RFQ messages use the Write bucket. See [Rate Limits and Tiers](/getting_started/rate_limits) for tier budgets and token-cost behavior. * Order-entry messages (35=D, 35=F, 35=G) carrying `ExDestination` (tag 100) with a value `>= 1` are billed to a [per-shard Write budget](/getting_started/rate_limits#sharded-exchanges-have-per-shard-write-budgets). RFQ quote accepts (35=D carrying `QuoteID`) always bill the unscoped Write budget. * Mass Cancel Request (35=q) with `530=6` is limited to 1 request/second. With `530=1` (one market) it uses the Write bucket at the same cost as an order cancel (35=F). ## Maintenance Window See [Maintenance and Pauses](/getting_started/maintenance_and_pauses) for scheduled maintenance times and the difference between trading pauses and exchange pauses. Sessions may be disconnected during the maintenance window. Kalshi does not initiate sequence number resets during maintenance; clients should reset sequence numbers on their side when reconnecting. KalshiRT sessions retain message continuity across the maintenance window. If your KalshiRT session is disconnected, you can request retransmission of any messages missed during the downtime after reconnecting. ### CancelOrderOnPause To control what happens to your resting orders during a [pause](/getting_started/maintenance_and_pauses), set tag `21006` (CancelOrderOnPause) on your **New Order Single (35=D)** messages: | Value | Behavior | | - | - | | Y | Order is automatically cancelled when a trading or exchange pause begins | | N (default) | Order remains resting on the book and resumes when activity reopens | This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.