PolymarketDocumentation/docs/developers/market-makers/trading.md

Documentation Index

Fetch the complete documentation index at: https://docs.polymarket.com/llms.txt Use this file to discover all available pages before exploring further.

Trading

CLOB order entry and management for market makers

Overview

Market makers primarily interact with Polymarket through the CLOB (Central Limit Order Book) API to post and manage limit orders.

Order Entry

Posting Limit Orders

Use the CLOB client to create and post limit orders:

import { ClobClient, Side, OrderType } from "@polymarket/clob-client";

const client = new ClobClient(
  "https://clob.polymarket.com",
  137,
  wallet,
  credentials,
  signatureType,
  funder
);

// Post a bid (buy order)
const bidOrder = await client.createAndPostOrder({
  tokenID: "34097058504275310827233323421517291090691602969494795225921954353603704046623",
  side: Side.BUY,
  price: 0.48,
  size: 1000,
  orderType: OrderType.GTC
});

// Post an ask (sell order)
const askOrder = await client.createAndPostOrder({
  tokenID: "34097058504275310827233323421517291090691602969494795225921954353603704046623",
  side: Side.SELL,
  price: 0.52,
  size: 1000,
  orderType: OrderType.GTC
});

See Create Order for full documentation.

Batch Orders

For efficiency, post multiple orders in a single request:

const orders = await Promise.all([
  client.createOrder({ tokenID, side: Side.BUY, price: 0.48, size: 500 }),
  client.createOrder({ tokenID, side: Side.BUY, price: 0.47, size: 500 }),
  client.createOrder({ tokenID, side: Side.SELL, price: 0.52, size: 500 }),
  client.createOrder({ tokenID, side: Side.SELL, price: 0.53, size: 500 })
]);

const response = await client.postOrders(
  orders.map(order => ({ order, orderType: OrderType.GTC }))
);

See Post Orders Batch for details.

Order Types

Type	Behavior	MM Use Case
GTC (Good Till Cancelled)	Rests on book until filled or cancelled	Default for passive quoting
GTD (Good Till Date)	Auto-expires at specified time	Auto-expire before events
FOK (Fill or Kill)	Fill entirely immediately or cancel	Aggressive rebalancing (all or nothing)
FAK (Fill and Kill)	Fill available immediately, cancel rest	Partial rebalancing acceptable

When to Use Each

For passive market making (maker orders):

• GTC - Standard quotes that sit on the book
• GTD - Time-limited quotes (e.g., expire before market close)

For rebalancing (taker orders):

• FOK - When you need exact size or nothing
• FAK - When partial fills are acceptable

// GTD example: expire in 1 hour
const expiringOrder = await client.createOrder({
  tokenID,
  side: Side.BUY,
  price: 0.50,
  size: 1000,
  orderType: OrderType.GTD,
  expiration: Math.floor(Date.now() / 1000) + 3600 // 1 hour from now
});

Order Management

Cancel Orders

Cancel individual orders or all orders:

// Cancel single order
await client.cancelOrder(orderId);

// Cancel multiple orders in a single calls
await client.cancelOrders(orderIds: string[]);

// Cancel all orders for a market
await client.cancelMarketOrders(conditionId);

// Cancel all orders
await client.cancelAll();

See Cancel Orders for full documentation.

Get Active Orders

Monitor your open orders:

// Get active order
const order = await client.getOrder(orderId);

// Get active orders optionally filtered
const orders = await client.getOpenOrders({
  id?: string; // Order ID (hash)
  market?: string; // Market condition ID
  asset_id?: string; // Token ID
});

See Get Active Orders for details.

Best Practices

Quote Management

1. Two-sided quoting - Post both bids and asks to earn maximum liquidity rewards
2. Monitor inventory - Skew quotes based on your position
3. Cancel stale quotes - Remove orders when market conditions change
4. Use GTD for events - Auto-expire quotes before known events

Latency Optimization

1. Batch orders - Use postOrders() instead of multiple createAndPostOrder() calls
2. WebSocket for data - Use WebSocket feeds instead of polling REST endpoints

Risk Management

1. Size limits - Check token balances before quoting; don't exceed inventory
2. Price guards - Validate against book midpoint; reject outlier prices
3. Kill switch - Use cancelAll() on error or position breach
4. Monitor fills - Subscribe to WebSocket user channel for real-time fill updates

Tick Sizes

Markets have different minimum price increments:

const tickSize = await client.getTickSize(tokenID);
// Returns: "0.1" | "0.01" | "0.001" | "0.0001"

Ensure your prices conform to the market's tick size.

Fee Structure

Role	Fee
Maker	0 bps
Taker	0 bps

Current fees are 0% for both makers and takers. See CLOB Introduction for fee calculation details.

Related Documentation

Complete client method reference Authenticated order management methods Real-time order and market data Earn rewards for providing liquidity