Most guides answer this question with a shrug: “start with whatever you're comfortable losing.” That's true but useless. Here's the answer with actual numbers: you can technically start with $10, you can learn properly with $50–100, and you need $500+ before the returns are worth the hours you'll put in. Let's break down why.

The technical minimum: about $10

Polymarket has no meaningful minimum deposit. Because it runs on Polygon, transaction (gas) costs are fractions of a cent, so even a $10 deposit doesn't get eaten by network fees the way it would on Ethereum mainnet. You could deposit $10, buy shares in two or three markets, and experience the full lifecycle: entry, price movement, resolution, payout.

What $10 won't give you is a real education. With positions of $3–5, you won't feel the sting of a bad trade or the discipline pressure of sizing decisions — and those are exactly the things you need to learn before betting real amounts.

The learning budget: $50–100

This is the sweet spot for a first month. Here's what it buys you:

  • 5–10 meaningful positions of $10–20 each, across different market types (politics, sports, crypto, current events)
  • Real emotional feedback. Losing $15 because you ignored the resolution criteria hurts enough to teach you; losing $2 doesn't.
  • Room for the inevitable beginner mistakes — buying at the ask in an illiquid market, holding a losing position too long, misreading what a market actually resolves on.

Rule of thumb: your first $100 is tuition, not investment capital. If you end month one down 20% but understand spreads, fees and resolution mechanics, you got a good deal.

What actually eats your money in 2026

Polymarket ended its zero-fee era in 2026, so budget for three costs:

CostHow muchHow to minimize it
Taker fees~0.75–1.8% per trade depending on category (sports lowest, crypto highest; geopolitics still free)Use limit orders — makers pay nothing
Spread1–5 cents per share in liquid markets; much more in thin onesTrade high-volume markets; use limit orders
Gas (Polygon)Under $0.01 per transactionNothing needed — it's negligible

The practical takeaway: if you place limit orders instead of hitting the market price, you avoid taker fees entirely and usually capture the spread instead of paying it. On a $100 bankroll making 20 trades, that's easily $20–30 saved over a few months — a 20–30% edge you get for free just from order discipline.

When returns start to matter: $500+

Here's the math nobody shows you. Suppose you become genuinely good and average a 5% monthly return — which would put you ahead of most traders:

  • On a $100 bankroll: $5/month. Nice, but it won't pay for your coffee habit.
  • On a $500 bankroll: $25/month. Now it's a hobby that pays for itself.
  • On a $2,000 bankroll: $100/month. Meaningful side income — and meaningful risk.

This is why we recommend the staged approach: learn on $50–100, and only scale up once you've had two or three consecutive months where you'd have been profitable even after fees. Scaling up a losing strategy just loses money faster.

Position sizing: the rule that protects any budget

Whatever your bankroll, the sizing rule stays the same: risk 1–5% of your bankroll per position, never more than 10%. On $100, that means $2–5 positions with a $10 absolute cap. Feels slow — and that's the point. The traders who blow up are almost never wrong about markets; they're wrong about sizing, putting 40% of their bankroll on one “sure thing” that wasn't.

Never trade money you can't afford to lose entirely. Prediction markets settle binary: winning shares pay $1.00, losing shares pay exactly $0. There is no partial credit, and positions in thin markets can be hard to exit early at a fair price.

A note for US readers

Since December 2025, Polymarket operates a regulated US platform (after its CFTC approval and QCX exchange acquisition), with full KYC and slightly different fees (~0.30% taker). The budget logic above applies the same way — the fees are lower, but sports contracts remain a legal battleground in some states, so check what's available where you live.

Bottom line

Start with $50–100 and treat it as tuition. Use limit orders to dodge taker fees. Size positions at 1–5% of bankroll. Scale to $500+ only after you've proven to yourself — with records, not vibes — that you're beating the market after fees. Skipping the small-money phase doesn't make you advanced; it just makes your tuition more expensive.

Want the full playbook? Our 168-page Complete Polymarket Guide ($9.99, updated July 2026) covers bankroll management, the exact fee structure, strategy selection and real trade case studies — or grab the free sample chapter first.