---
updatedAt: 2026-04-26T11:06:29.000Z
agentTools:
  projectIndex: https://apidocs.bct.host/llms.txt
---

# Fiat Deposit API

Submit a fiat deposit notification.

# OpenAPI definition

```json
{
  "openapi": "3.0.3",
  "info": {
    "title": "OSL HK Fiat API",
    "version": "1.0.0",
    "description": "HK site fiat API converted literally from the supplied English Markdown documentation."
  },
  "servers": [
    {
      "url": "https://trade-hk.oslsandbox.com",
      "description": "OPEN_API_HOST"
    }
  ],
  "tags": [
    {
      "name": "Fiat",
      "description": "Fiat Deposit, Withdrawal, and Query APIs"
    }
  ],
  "security": [
    {
      "RestKey": [],
      "RestSign": []
    }
  ],
  "components": {
    "securitySchemes": {
      "RestKey": {
        "type": "apiKey",
        "in": "header",
        "name": "Rest-Key",
        "description": "API Key"
      },
      "RestSign": {
        "type": "apiKey",
        "in": "header",
        "name": "Rest-Sign",
        "description": "HMAC-SHA512 signature of the request body"
      }
    }
  },
  "paths": {
    "/api/3/deposit/fiat": {
      "post": {
        "tags": [
          "Fiat"
        ],
        "summary": "Fiat Deposit API",
        "description": "Submit a fiat deposit notification.",
        "operationId": "submitFiatDeposit",
        "parameters": [
          {
            "name": "Rest-Key",
            "in": "header",
            "required": true,
            "schema": {
              "type": "string"
            },
            "description": "API Key"
          },
          {
            "name": "Rest-Sign",
            "in": "header",
            "required": true,
            "schema": {
              "type": "string"
            },
            "description": "HMAC-SHA512 signature of the request body"
          },
          {
            "name": "Content-Type",
            "in": "header",
            "required": true,
            "schema": {
              "type": "string",
              "enum": [
                "application/json"
              ]
            },
            "description": "`application/json`"
          }
        ],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "properties": {
                  "tonce": {
                    "type": "string",
                    "description": "Current Unix time in microseconds, used for replay protection."
                  },
                  "ccy": {
                    "type": "string",
                    "description": "Fiat currency ticker (`USD`, `HKD` currently)."
                  },
                  "amount": {
                    "type": "number",
                    "description": "Deposit amount. Must be > 0, max 2 decimal places."
                  },
                  "accountGroupUuid": {
                    "type": "string",
                    "description": "Account group UUID."
                  }
                },
                "required": [
                  "ccy",
                  "amount",
                  "accountGroupUuid"
                ]
              },
              "examples": {
                "Request": {
                  "value": {
                    "tonce": "8888888888000",
                    "ccy": "USD",
                    "accountGroupUuid": "5bd869fe-4898-472d-be9b-a4e294bc8c81",
                    "amount": 66.81
                  }
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Success or business error response.",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "timestamp": {
                      "type": "integer",
                      "description": ""
                    },
                    "resultCode": {
                      "type": "string",
                      "enum": [
                        "OK"
                      ],
                      "description": "`OK` on success."
                    },
                    "depositCode": {
                      "type": "string",
                      "description": "Unique deposit code for tracking."
                    },
                    "amount": {
                      "type": "number",
                      "description": "Deposit amount."
                    },
                    "ccy": {
                      "type": "string",
                      "description": "Currency ticker."
                    },
                    "status": {
                      "type": "string",
                      "enum": [
                        "SUBMITTED"
                      ],
                      "description": "Deposit status. Always `SUBMITTED` on creation."
                    },
                    "accountGroupUuid": {
                      "type": "string",
                      "description": "Account group UUID."
                    },
                    "bizTime": {
                      "type": "string",
                      "description": "UTC+8 TZ ,Business date (`yyyy-MM-dd HH:mm:ss`)."
                    }
                  },
                  "required": [
                    "timestamp",
                    "resultCode",
                    "depositCode",
                    "amount",
                    "ccy",
                    "status",
                    "accountGroupUuid",
                    "bizTime"
                  ]
                },
                "examples": {
                  "Success": {
                    "summary": "200 Success",
                    "value": {
                      "timestamp": 1745316606208,
                      "resultCode": "OK",
                      "depositCode": "AXPWX1153209",
                      "amount": 10000,
                      "ccy": "USD",
                      "status": "SUBMITTED",
                      "accountGroupUuid": "5bd869fe-4898-472d-be9b-a4e294bc8c81",
                      "bizTime": "2026-04-22 17:10:06"
                    }
                  }
                }
              }
            }
          }
        },
        "x-errorResponses": [
          {
            "resultCode": "RESTIRCTED_FIAT_PAYMENT_IN",
            "httpStatus": 200,
            "description": "Fiat deposit API is disabled (circuit breaker).   User is restricted from fiat deposits or is crypto-only verified."
          },
          {
            "resultCode": "UNAUTHORISED",
            "httpStatus": 200,
            "description": "Invalid API key or signature."
          },
          {
            "resultCode": "NO_PERMISSION",
            "httpStatus": 200,
            "description": "API key does not have `moveFunds` permission."
          },
          {
            "resultCode": "RESTRICTED_PAYMENT_IN",
            "httpStatus": 200,
            "description": "User or account group is restricted from deposits."
          },
          {
            "resultCode": "INVALID_PARAMETERS",
            "httpStatus": 200,
            "description": "Invalid request parameters (missing fields, invalid amount, etc.)."
          },
          {
            "resultCode": "UNSUPPORTED_CCY",
            "httpStatus": 200,
            "description": "Currency is not a supported fiat currency."
          },
          {
            "resultCode": "ACCOUNT_GROUP_NOT_FOUND",
            "httpStatus": 200,
            "description": "Account group not found or user has no access."
          },
          {
            "resultCode": "SYSTEM_ERROR",
            "httpStatus": 200,
            "description": "Deposit engine is off or internal error."
          }
        ]
      }
    }
  },
  "x-readme": {}
}
```