Phase 1: Pre-Trade

The pre-trade phase covers customer account onboarding, cash balance auditing, SOD transaction verification (corporate actions, stock transfers), margin calculations, instrument reference data discovery, overnight option quote/trade snapshots, and real-time WebSocket subscriptions.

note

All pre-trade REST requests require authentication via the X-API-KEY header and an account_number parameter.

1.1 Account Onboarding & Information

Step	Action	Method & Path	Description
1.1.1	Create End Customer Account	POST /accounts/ec/create	Register a new end-customer account under your initiator account.
1.1.2	Fetch End Customer Accounts	GET /accounts/ec	Retrieve list of registered end-customer accounts.
1.1.3	Fetch Accounts	GET /accounts	List accounts accessible by the authenticated API key.

1.2 Account Cash Balances, SOD Transactions & Margin Verification

Step	Action	Method & Path	Description
1.2.1	Check Account Cash & Balances	GET /balances	Query account balances including cash_available, cash_secured, and cash_withheld.
1.2.2	Audit SOD Transactions & Corporate Actions	GET /transactions	Fetch Start-of-Day (SOD) transactions (e.g. corporate actions, stock transfers, cash adjustments) to reconcile opening portfolio state.
1.2.3	Verify House Margin	GET /house-margin	Retrieve total house margin requirement summary for an account.
1.2.4	Check House Margin Details	GET /house-margin-details	Fetch detailed component breakdown of house margin requirements.
1.2.5	Check ClearStreet Margin	GET /house-margin/clearstreet	Fetch ClearStreet clearing house margin requirement status.

1.3 Market Status & Security Reference Data

Step	Action	Method & Path	Description
1.3.1	Check Market Status	GET /market/status	Confirm market operational session.
1.3.2	Fetch Equity Securities	GET /equities	Download active daily equity instruments reference data.
1.3.3	Fetch Option Securities	GET /options	Download active daily option contracts reference data.
1.3.4	Fetch Option Underliers	GET /option-underliers	Retrieve underlier symbols and tier parameters for options.

1.4 Overnight Options (US Only)

Step	Action	Method & Path	Description
1.4.1	Overnight Active Underliers	GET /overnight/active-underliers	Query list of symbols active for overnight options trading.
1.4.2	Overnight Option Quotes Snapshot	GET /overnight/quotes/option	Fetch snapshot quotes for overnight options contracts.
1.4.3	Overnight Option Trades History	GET /overnight/trades/option	Fetch recent trade history for overnight options.
1.4.4	Connect Option Quotes WebSocket	GET /websocket/quotes/option	Open WebSocket stream for live streaming overnight option level-1 quotes.
1.4.5	Connect Option Trades WebSocket	GET /websocket/trades/option	Open WebSocket stream for live streaming overnight option trades.

1.5 Account Event Data Streaming

Step	Action	Method & Path	Description
1.5.1	Connect Account Event WebSocket	GET /websocket	Open WebSocket connection for real-time order updates.

For details on connecting and handling WebSocket messages, see the WebSocket guide.