Create Order

curl --request POST \
  --url https://api.limitless.exchange/orders \
  --header 'Content-Type: application/json' \
  --header 'lmts-api-key: <api-key>' \
  --data '
{
  "order": {
    "salt": "1778155025318314496",
    "maker": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
    "signer": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
    "taker": "0x0000000000000000000000000000000000000000",
    "tokenId": "19633204485790857949828516737993423758628930235371629943999544859324645414627",
    "makerAmount": 5000000,
    "takerAmount": 10000000,
    "expiration": "0",
    "nonce": 0,
    "price": 0.5,
    "feeRateBps": 0,
    "side": 0,
    "signature": "0x6e3a3f2c2c2bb1ce3a14c4f5e4ad6f3c8b1ad9c44d4d5fa1c4cd5b6e74a4d4a36cc4ad9c44d4d5fa1c4cd5b6e74a4d4a36cc4ad9c44d4d5fa1c4cd5b6e74a4d41b",
    "signatureType": 2
  },
  "ownerId": 12345,
  "orderType": "GTC",
  "marketSlug": "biden-vs-trump-2024",
  "clientOrderId": "client-order-001"
}
'

{
  "order": {
    "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "salt": "1778155025318314496",
    "maker": "<string>",
    "signer": "<string>",
    "tokenId": "<string>",
    "signature": "<string>",
    "marketId": "<string>",
    "ownerId": 123,
    "createdAt": "2023-11-07T05:31:56Z",
    "market": {
      "id": 123,
      "slug": "<string>",
      "title": "<string>",
      "yesPositionId": "<string>",
      "noPositionId": "<string>",
      "group": {
        "id": 123,
        "slug": "<string>",
        "title": "<string>"
      }
    },
    "makerAmount": 5000000,
    "takerAmount": 10000000,
    "nonce": 0,
    "owner": {
      "id": 123,
      "account": "<string>",
      "client": "<string>",
      "smartWallet": "<string>",
      "username": "<string>",
      "displayName": "<string>",
      "pfpUrl": "<string>",
      "socialUrl": "<string>",
      "rankName": "<string>",
      "points": 123,
      "referredUsersCount": 123,
      "isTop100": true,
      "leaderboardPosition": 123
    },
    "taker": "<string>",
    "expiration": "2023-11-07T05:31:56Z",
    "feeRateBps": 123,
    "price": 0.75
  },
  "execution": {
    "matched": true,
    "settlementStatus": "MINED",
    "feeRateBps": 25,
    "effectiveFeeBps": 26,
    "totalsRaw": {
      "contractsGross": "1000000",
      "contractsFee": "1000",
      "contractsNet": "999000",
      "usdGross": "500000",
      "usdFee": "500",
      "usdNet": "499500"
    },
    "reason": "settlement transaction reverted",
    "eligibleAt": "2026-06-08T10:15:30.000Z",
    "tradeEventId": "4aa706dd-6c57-4f3c-945a-99818dfd95f1",
    "txHash": "0xabc123",
    "clientOrderId": "client-order-001",
    "stpMakerCancels": [
      "4aa706dd-6c57-4f3c-945a-99818dfd95f1"
    ]
  },
  "makerMatches": [
    {
      "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
      "matchedSize": "1000000",
      "fillPrice": "0.55",
      "fillCost": "550000",
      "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
      "order": {
        "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
        "maker": "<string>",
        "price": "0.55",
        "tokenId": "<string>",
        "owner": {
          "id": 123,
          "account": "<string>",
          "client": "<string>",
          "smartWallet": "<string>",
          "username": "<string>",
          "displayName": "<string>",
          "pfpUrl": "<string>",
          "socialUrl": "<string>",
          "points": 0,
          "referredUsersCount": 0
        }
      }
    }
  ]
}

POST

orders

curl --request POST \
  --url https://api.limitless.exchange/orders \
  --header 'Content-Type: application/json' \
  --header 'lmts-api-key: <api-key>' \
  --data '
{
  "order": {
    "salt": "1778155025318314496",
    "maker": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
    "signer": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
    "taker": "0x0000000000000000000000000000000000000000",
    "tokenId": "19633204485790857949828516737993423758628930235371629943999544859324645414627",
    "makerAmount": 5000000,
    "takerAmount": 10000000,
    "expiration": "0",
    "nonce": 0,
    "price": 0.5,
    "feeRateBps": 0,
    "side": 0,
    "signature": "0x6e3a3f2c2c2bb1ce3a14c4f5e4ad6f3c8b1ad9c44d4d5fa1c4cd5b6e74a4d4a36cc4ad9c44d4d5fa1c4cd5b6e74a4d4a36cc4ad9c44d4d5fa1c4cd5b6e74a4d41b",
    "signatureType": 2
  },
  "ownerId": 12345,
  "orderType": "GTC",
  "marketSlug": "biden-vs-trump-2024",
  "clientOrderId": "client-order-001"
}
'

{
  "order": {
    "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "salt": "1778155025318314496",
    "maker": "<string>",
    "signer": "<string>",
    "tokenId": "<string>",
    "signature": "<string>",
    "marketId": "<string>",
    "ownerId": 123,
    "createdAt": "2023-11-07T05:31:56Z",
    "market": {
      "id": 123,
      "slug": "<string>",
      "title": "<string>",
      "yesPositionId": "<string>",
      "noPositionId": "<string>",
      "group": {
        "id": 123,
        "slug": "<string>",
        "title": "<string>"
      }
    },
    "makerAmount": 5000000,
    "takerAmount": 10000000,
    "nonce": 0,
    "owner": {
      "id": 123,
      "account": "<string>",
      "client": "<string>",
      "smartWallet": "<string>",
      "username": "<string>",
      "displayName": "<string>",
      "pfpUrl": "<string>",
      "socialUrl": "<string>",
      "rankName": "<string>",
      "points": 123,
      "referredUsersCount": 123,
      "isTop100": true,
      "leaderboardPosition": 123
    },
    "taker": "<string>",
    "expiration": "2023-11-07T05:31:56Z",
    "feeRateBps": 123,
    "price": 0.75
  },
  "execution": {
    "matched": true,
    "settlementStatus": "MINED",
    "feeRateBps": 25,
    "effectiveFeeBps": 26,
    "totalsRaw": {
      "contractsGross": "1000000",
      "contractsFee": "1000",
      "contractsNet": "999000",
      "usdGross": "500000",
      "usdFee": "500",
      "usdNet": "499500"
    },
    "reason": "settlement transaction reverted",
    "eligibleAt": "2026-06-08T10:15:30.000Z",
    "tradeEventId": "4aa706dd-6c57-4f3c-945a-99818dfd95f1",
    "txHash": "0xabc123",
    "clientOrderId": "client-order-001",
    "stpMakerCancels": [
      "4aa706dd-6c57-4f3c-945a-99818dfd95f1"
    ]
  },
  "makerMatches": [
    {
      "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
      "matchedSize": "1000000",
      "fillPrice": "0.55",
      "fillCost": "550000",
      "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
      "order": {
        "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
        "maker": "<string>",
        "price": "0.55",
        "tokenId": "<string>",
        "owner": {
          "id": 123,
          "account": "<string>",
          "client": "<string>",
          "smartWallet": "<string>",
          "username": "<string>",
          "displayName": "<string>",
          "pfpUrl": "<string>",
          "socialUrl": "<string>",
          "points": 0,
          "referredUsersCount": 0
        }
      }
    }
  ]
}

Before creating orders:

Fetch market data via Get Market Details to get venue and token IDs
Sign the order using EIP-712 with venue.exchange as verifyingContract
Ensure you have token approvals set up

Order creation can be temporarily restricted during maintenance. In post_only, only orders with postOnly: true are accepted. In cancel_only or disabled, new orders return 425 Too Early with a trading-mode code. Check Maintenance Mode before sending orders.

Authentication

Use a scoped API token with HMAC signing and the trading scope.

Signed order rules

For client-signed orders, signature and signatureType are both required. They must either both be present or both be omitted. Omission is accepted only for delegated server signing with an HMAC token carrying delegated_signing. nonce is required and must be the numeric value 0. expiration may be omitted; omission is signed as zero. If supplied, it must represent zero, for example "0". Non-zero expiration is not supported. Amounts are integer raw units with 6 decimals. makerAmount must be at least 100 raw units. For GTC and FAK orders, price is required, must be between 0.01 and 0.99, and may have at most three decimal places. The collateral equation must be exact. price × contracts must be an integer raw-unit amount, without rounding.

Type	BUY amounts	SELL amounts	Price
`GTC` / `FAK`	`makerAmount = price × contracts`; `takerAmount = contracts`	`makerAmount = contracts`; `takerAmount = price × contracts`	Required
`FOK`	`makerAmount = maximum collateral to spend`; `takerAmount = 1`	`makerAmount = shares to sell`; `takerAmount = 1`	Must be omitted

postOnly is supported only for GTC orders.

Optional fields

Field	Type	Description
`clientOrderId`	`string`	Optional uniqueness and deduplication key. The submitted value may contain at most 128 characters; it is then trimmed and must not be blank. Reuse returns `409 Conflict`; the API does not replay the earlier response.
`onBehalfOf`	`number`	Profile ID of the sub-account to place the order for. Requires a scoped API token with `trading` scope and a partner relationship with the target profile. The `maker` and `signer` in the order must match the sub-account’s wallet address.
`postOnly`	`boolean`	GTC orders only. When `true`, the order is rejected if it would immediately match. Guarantees the order rests on the book as a maker order. Default `false`.
`timestamp`	`number`	Optional client-stamped Unix time in milliseconds for receive-window checks. Top-level request field; not part of the signed `order`.
`recvWindow`	`number`	Optional maximum accepted order age in milliseconds, up to `10000`. If omitted, the API default applies. Top-level request field; not part of the signed `order`.
`stpPolicy`	`string`	Self-trade prevention policy. Values: `cancel_maker`, `cancel_taker`, `cancel_both`. Default `cancel_maker`. Top-level request field; not part of the signed `order`.

Receive window

POST /orders supports optional receive-window controls for clients that want freshness checks on order submission. Send these fields at the top level of the request body, next to order, orderType, and marketSlug; never put them inside the EIP-712 signed order object.

{
  "order": {
    "...": "signed order fields"
  },
  "orderType": "GTC",
  "marketSlug": "btc-100k",
  "timestamp": 1779870000000,
  "recvWindow": 1500
}

Field	Description
`timestamp`	Client order creation time as Unix milliseconds. Send it with a nonzero effective `recvWindow` to enforce client-to-server freshness. If omitted while a window applies, the server uses its receive time.
`recvWindow`	Maximum accepted age, in milliseconds, between the effective timestamp and server receive time, up to `10000`. If omitted, the API default applies. A timestamp alone has no freshness effect when the effective window is zero.

Keep trading hosts NTP-synced. If the timestamp is too far in the future or older than the receive window, the API returns 425 Too Early. Do not retry the same signed payload after a receive-window 425; build and sign a fresh order. If the 425 body has a trading-mode code, refresh maintenance status instead.

Self-trade prevention

POST /orders can reject or cancel orders that would match against your own resting order on the same token.

{
  "order": {
    "...": "signed order fields"
  },
  "orderType": "GTC",
  "marketSlug": "btc-100k",
  "stpPolicy": "cancel_taker"
}

Policy	Result
`cancel_maker`	Default. Cancel your conflicting resting order and continue with the incoming order.
`cancel_taker`	Reject the incoming order before it self-trades.
`cancel_both`	Cancel your conflicting resting order and reject the incoming order.

With cancel_maker, matching continues against the remaining non-self liquidity, and limit orders still never execute past their limit price. Outcomes on the placement response:

A rejected taker (cancel_taker / cancel_both) returns settlementStatus: "CANCELED" with reason: "STP_TAKER_REJECTED".
A cancel_maker taker lists the canceled resting order IDs in stpMakerCancels and keeps its normal status (UNMATCHED when nothing else fills it); no reason is set.

stpPolicy is a top-level request field. Do not include it inside the EIP-712 signed order object.

SDK support. Self-trade prevention is available in the TypeScript, Python, Rust, and Go SDKs. Pass the policy on order creation and read the outcome from the execution object on the response. See TypeScript, Python, Rust, and Go.

Where does ownerId come from? It is the id field returned by GET /profiles/me or GET /profiles/{address}. For partner sub-accounts, it is the profileId returned by POST /profiles/partner-accounts, or recovered with GET /profiles/partner-accounts.

ownerId must match the profile that owns the order (see Programmatic API — EOA flow):

Partner EOA + signed order + onBehalfOf: set both onBehalfOf and ownerId to the sub-account’s profileId. order.maker and order.signer must match that sub-account’s wallet. A mismatched ownerId returns 400 with the message "Profile ID does not match the order owner".
Delegated signing (unsigned order, delegated_signing scope, server wallet sub-account): send the target profile ID as both onBehalfOf and ownerId. The server normalizes ownerId to that target when it signs. Omit the client signature per Delegated signing below.
Trading as yourself (no onBehalfOf): ownerId is your own profile id (the SDK often fills this after fetching your profile).
Signer does not match - you should use embedded address for smart wallet: your profile is in smart-wallet trading mode, which self-signed API orders can’t satisfy. Switch to EOA mode. See Trading wallet mode.

Delegated signing

Partners place orders for a managed sub-account by setting body onBehalfOf to its profile ID. A client-signed order requires trading; the target must belong to the authenticated partner. With both trading and delegated_signing, partners may instead omit both signature and signatureType. The request must still include the target profile ID as both onBehalfOf and ownerId. The server signs using a Privy server wallet linked to that profile, replaces maker and signer with that wallet address, and normalizes ownerId to the target. See Authentication.

Execution response

The response includes an execution object with settlement details:

Field	Type	Description
`matched`	`boolean`	Whether the order was matched immediately
`settlementStatus`	`string`	`UNMATCHED`, `MATCHED`, `MINED`, `CONFIRMED`, `RETRYING`, `FAILED`, `DELAYED`, or `CANCELED`
`reason`	`string`	Free-form terminal detail. For example, `STP_TAKER_REJECTED` accompanies an STP-canceled taker; settlement or recovery failures can return other text with `FAILED`.
`eligibleAt`	`string`	ISO-8601 time the order is released to the matching engine. Present only when `settlementStatus` is `DELAYED` (taker delay).
`tradeEventId`	`string`	Trade event ID (present when matched)
`txHash`	`string`	On-chain transaction hash (present when mined)
`stpMakerCancels`	`string[]`	Resting order IDs canceled by self-trade prevention (present when `cancel_maker` / `cancel_both` canceled one or more of your resting orders)
`feeRateBps`	`number`	Fee rate in basis points
`effectiveFeeBps`	`number`	Effective fee rate after rebates
`totalsRaw`	`object`	Raw execution totals (`contractsGross`, `contractsFee`, `contractsNet`, `usdGross`, `usdFee`, `usdNet`)

DELAYED (taker delay). Some markets apply a short hold to marketable (taker) orders before the matching engine fills them. On such a market, a marketable order’s response returns immediately with settlementStatus: "DELAYED", matched: false, zero totalsRaw, and an eligibleAt timestamp. It does not block until the trade is mined. Track the outcome over subscribe_order_events (provisional MATCHED → terminal MINED / FAILED), correlating by clientOrderId / tradeEventId. postOnly orders are never delayed.

Errors

Status	Meaning
`400`	Structural validation, invalid signature/owner/token/amounts, insufficient balance or allowance, unavailable/resolved/expired market, delegated-signing failure, or matching-engine rejection. Validation failures use a `message` array; business failures usually use a string. Missing markets and profiles are normalized to `400` on this endpoint.
`401`	Authentication failed.
`403`	The HMAC token lacks `trading`, or `onBehalfOf` is not an authorized partner target.
`409`	`clientOrderId` or the signed order hash already exists or is being processed.
`425`	Receive-window rejection or a maintenance trading mode that blocks creation. Receive-window bodies contain a message; maintenance bodies contain a trading-mode `code`.
`500`	Unexpected order-creation failure.

Authorizations

lmts-api-key

string

header

required

Scoped API token with HMAC-SHA256 signing. Requires three headers: lmts-api-key (token ID), lmts-timestamp (ISO-8601), lmts-signature (Base64-encoded HMAC). See Authentication docs for details.

Body

application/json

Order creation data including signature and order parameters

order

object

required

Order details including signature and amounts

Option 1
Option 2

Show child attributes

ownerId

integer

required

Required profile ID of the order owner. For delegated signing, send the target profile ID as both ownerId and onBehalfOf.

Example:

12345

orderType

enum<string>

required

Order type (GTC=Good Till Cancelled, FAK=Fill And Kill, FOK=Fill Or Kill)

Available options:

FAK,

FOK,

GTC

Example:

"GTC"

marketSlug

string

required

Market identifier slug

Example:

"biden-vs-trump-2024"

postOnly

boolean

Reject the order if it would match immediately. Supported only for GTC orders.

Example:

true

clientOrderId

string

Optional owner-scoped uniqueness and deduplication key. The submitted value is limited to 128 characters, then trimmed; blank values are rejected. Reuse returns 409 rather than replaying an earlier response.

Maximum string length: 128

Example:

"client-order-001"

onBehalfOf

integer

Managed profile ID for partner placement. Requires trading and a partner relationship; unsigned delegated placement also requires delegated_signing.

Required range: x >= 1

Example:

12345

timestamp

integer

Optional client-stamped order creation time, Unix ms epoch. Top-level request field; not part of the EIP-712 signed order payload.

Required range: x >= 0

Example:

1735689600000

recvWindow

integer

Optional maximum order age in milliseconds, up to 10000. If omitted, the API default applies. A supplied window without timestamp uses server receive time.

Required range: 1 <= x <= 10000

Example:

1500

stpPolicy

enum<string>

Self-trade prevention policy. Top-level request field; not part of the EIP-712 signed order payload. Defaults to cancel_maker when omitted.

Available options:

cancel_both,

cancel_maker,

cancel_taker

Example:

"cancel_maker"

Response

Order accepted. It may be resting, delayed, matched, settled, canceled by STP, or accepted with a settlement failure reported in execution.

order

object

required

Order details including slim market and owner

Show child attributes

execution

object

required

Execution and settlement summary

Show child attributes

makerMatches

object[]

Maker matches if order was matched immediately

Show child attributes

⌘I

Overview

System

Authentication

Markets

Trading

Portfolio

Market Pages & Navigation

API Tokens

Partner Accounts

Public Portfolio

Referral

Leaderboard

Authentication

Signed order rules

Optional fields

Receive window

Self-trade prevention

Delegated signing

Execution response

Errors

Authorizations

Body

Response

​Authentication

​Signed order rules

​Optional fields

​Receive window

​Self-trade prevention

​Delegated signing

​Execution response

​Errors

Authorizations

Body

Response

Authentication

Signed order rules

Optional fields

Receive window

Self-trade prevention

Delegated signing

Execution response

Errors