---
title: "Submit register trader transaction"
method: POST
path: "/v1/exchange/send-register-ixs"
tags: ["Exchange"]
---

# Submit register trader transaction

`POST /v1/exchange/send-register-ixs`

Validates a base64-encoded transaction for the default trader account, signs it with the Phoenix onboarder, simulates it to ensure the onboarder pays no lamports, sends it to Phoenix's RPC, and returns the transaction signature.

## Request body

- SendRegisterIxsRequest — Request payload for /exchange/send-register-ixs.
  - `maxPositions` integer, nullable
  - `traderAuthority` string, required
  - `traderPdaIndex` integer, nullable
  - `traderSubaccountIndex` integer, nullable
  - `transaction` string, required — Base64-encoded Solana transaction wire bytes signed by the user-owned required signers. The API validates, signs as onboarder, simulates, and submits it.
  - `txFeePayer` string, required

## Response `200`

- SendRegisterIxsResponse — Response payload for /exchange/send-register-ixs.
  - `includeRegisterTrader` boolean, required
  - `maxPositions` integer, required
  - `signature` string, required
  - `traderOnboarder` string, required
  - `traderPda` string, required
  - `txFeePayer` string, required

---

[API](https://skmtc.net/phoenix/apis/phoenix-eternal-api.md) · [All operations](https://skmtc.net/phoenix/apis/phoenix-eternal-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/phoenix/phoenix-eternal-api/revisions/0f598402d680/schema)