Polymarket Market Making: Earn from Spreads and Rebates
Market making on Polymarket means posting both buy (bid) and sell (ask) orders on the same market and profiting from the spread between them. You also earn daily maker rebates from Polymarket. This is a capital-intensive strategy that generates consistent, small returns but requires careful inventory management and risk control.
How Market Making Works
You post a bid at, say, $0.48 and an ask at $0.52 on a YES market. When a buyer takes your ask, you sell a share at $0.52. When a seller takes your bid, you buy a share at $0.48. Each round-trip earns you $0.04 (the spread).
The challenge is managing inventory. If the market moves against you, you may accumulate too many shares on one side. Professional market makers use hedging, dynamic pricing, and position limits to manage this risk.
Revenue Sources
| Source | How It Works | Typical Yield |
|---|---|---|
| Bid-ask spread | Profit from the difference between buy and sell prices | $0.02-$0.05 per round-trip |
| Maker rebates | Polymarket redistributes taker fees to makers daily | 2-3% of taker fees on your market |
| Information flow | Adjusting quotes ahead of price moves | Variable (skill-dependent) |
Capital Requirements
Market making requires significant capital because you need to post orders on both sides of the book. For a single market, you need at least $500-$1,000 to post meaningful quotes. Professional market makers deploy $50,000+ across multiple markets.
Your capital is actively at risk because you are holding inventory (shares) that can lose value if the market moves against you. Unlike arbitrage, market making is not risk-free.
Key Risks
- Adverse selection: Informed traders trade against your quotes when they know the price is about to move. You buy shares that are about to drop or sell shares about to rise
- Inventory risk: Accumulating too many shares on one side exposes you to directional risk
- Event resolution: If you are holding shares when a market resolves, your inventory may become worthless
- Competition: Professional market makers with better algorithms squeeze your margins
- Capital lockup: Your capital is tied up in open orders and inventory, limiting flexibility
Getting Started
- Choose liquid markets with high trading volume and moderate volatility
- Start with wide spreads ($0.04-$0.06) and narrow them as you gain experience
- Set maximum inventory limits (e.g., never hold more than 500 shares on either side)
- Monitor your positions frequently and adjust quotes when the market moves
- Track your P&L daily, separating spread income from inventory gains/losses
Frequently Asked Questions
How much can I earn market making on Polymarket?
Returns depend on capital deployed, spread width, and volume. A typical retail market maker posting $5,000 across 5-10 markets might earn 0.5-2% per week, or 25-100% annualized. However, a single large adverse move can wipe out weeks of spread income.
Do I need a bot to market make?
Not strictly, but it helps enormously. Manual market making requires constant attention and fast reactions. Most successful market makers use automated systems to post and adjust quotes. Polymarket's API supports programmatic trading.
What is adverse selection?
Adverse selection means informed traders selectively trade against your quotes when they have better information. For example, if breaking news makes YES more likely, informed buyers take your YES asks before you can adjust your price.
How is market making different from arbitrage?
Arbitrage locks in risk-free profit by buying both sides simultaneously. Market making posts orders on both sides and hopes they fill at different times, profiting from the spread. Market making carries inventory risk; arbitrage does not.