Trading Fees

ProphetX charges a fee on filled orders using one of two models. Which model and rate apply to your account is configured on ProphetX's side — there's no field on submit_order to choose it, and no endpoint to query your current rate. If you're not sure which model your account is on, ask your ProphetX integration contact.

This page covers fees on regular fills. Closing a position through Positions is charged differently — a flat percentage of profit only, never your account's maker/taker or commission rate, and never charged on a loss or breakeven close.

The two models

Telling maker from taker

The API doesn't return a role field on a fill, but you can derive it from what you already control:

• An ALO (Add-Liquidity-Only) order is always maker — it's rejected rather than allowed to take, so any fill it gets was passive. See order_strategy. Over FIX, the equivalent is ExecInst(18)=6 (make-only) — see §5.1.
• A market order is always taker — by definition it crosses into existing liquidity.
• A plain limit order is maker if it rested on the book and was later taken by someone else, and taker if it crossed and matched immediately on entry.

Where the fee shows up

The examples below all follow the same order, so the numbers tie together across surfaces: a $30 maker order on MLB event 10079773, market 219, at price 120, that fills in three $10 pieces charging 0.04, 0.04, and 0.05 — a 0.13 total.

REST. The dollar amount you were actually charged — already resolved under whichever model applies to you — is in the fee field.

GET /v4/mm/get_trades and GET /v4/mm/get_order_matched_detail — the fee for one specific fill:

{
  "data": {
    "trades": [
      {
        "id": 918273645,
        "order_id": "partner_8900af46-2b89-40fa-a27a-ff65fcb437d2",
        "price": 120,
        "quantity": 10,
        "profit": 12,
        "fee": 0.04,
        "strike": null,
        "strike_id": "cffa7ddc4fd50acbe51684e7addabe00",
        "status": "settled",
        "winning_status": "tbd",
        "matched_at": "2026-10-06T07:12:03Z"
      }
    ],
    "next_cursor": null
  }
}

GET /v4/mm/get_order_history and GET /v4/mm/get_order/{id} — the order's total fee across all three fills (the same object; get_order_history wraps it in a data.orders[] list, get_order/{id} returns it directly under data):

{
  "data": {
    "order_id": "partner_8900af46-2b89-40fa-a27a-ff65fcb437d2",
    "sport_event_id": 10079773,
    "market_id": 219,
    "outcome_id": 4,
    "price": 120,
    "quantity": 30,
    "filled_quantity": 30,
    "open_quantity": 0,
    "profit": 36,
    "fee": 0.13,
    "status": "settled",
    "matching_status": "fully_matched",
    "winning_status": "tbd",
    "strike_id": "cffa7ddc4fd50acbe51684e7addabe00"
  },
  "last_synced_at": "2026-10-06T07:12:05Z"
}

WebSocket. The private orders event carries the same running total as fee, updated on every fill — see Private user channel. It's only present if you registered for v2 (CFTC-vocabulary) messages; the legacy v1 wagers feed never carries it. This frame is the fill confirming the first $10 piece, so fee is 0.04 — not yet the order's 0.13 total:

{
  "aggressive": false,
  "fee": 0.04,
  "fill_price": 120,
  "filled_quantity": 10,
  "matching_status": "partially_matched",
  "open_quantity": 20,
  "price": 120,
  "quantity": 30,
  "total_filled_quantity": 10,
  "update_type": "matching",
  "sport_event_id": 10079773,
  "status": "open",
  "user_id": "<redacted>"
}

The public trade_execution/matched_bet broadcast — the anonymized tape every participant receives — deliberately does not include fee: it's not account-specific data, and exposing it there would leak your commercial terms to everyone else on the feed.

FIX. The same fee rides on the Execution Report: Commission(12) is this fill's fee (sent only when it's nonzero), and the custom CumulativeFee(6002) tag is the running total across all fills on the order. FIX is tag=value, not JSON — the Trade report for that same first fill carries:

ExecType(150)=F  OrdStatus(39)=1  LastQty(32)=10  LastPx(31)=120
Commission(12)=0.04  CommType(13)=3  CumulativeFee(6002)=0.04

See Execution Report in the FIX Order Entry spec.

Wallet. A maker_taker fee posts as a FEE transaction (transaction_sub_type: MAKER_TAKER); a commission fee posts as COMMISSION — see transaction types. The ledger row for that same first fill:

{
  "data": {
    "transactions": [
      {
        "status": "Completed",
        "user_id": "550e8400-e29b-41d4-a716-446655440000",
        "transaction_type": "FEE",
        "transaction_sub_type": "MAKER_TAKER",
        "amount": 0.04,
        "change": -0.04,
        "balance": 999.96,
        "balance_before": 1000.00,
        "details": "4b6e2f1a-7c3d-4e8a-9f2b-1d5c6a8b9e0f",
        "market_id": "219",
        "event_id": "10079773",
        "trade_id": "918273645",
        "description": "Maker/taker fee",
        "created_at": "2026-10-06T07:12:03Z"
      }
    ],
    "next_cursor": null
  }
}