Polymarket Bot Fees Explained: Flat Rates, Odds Curves, and Subscriptions

Last updated 2026-07-15 · methodology · changelog

Polymarket bots price trades three ways: a flat percentage, a curve that varies with the odds, or a subscription stacked on top of per-trade fees. Which one is cheapest depends on where on the odds spectrum you actually trade — so this guide does the arithmetic.

The three pricing models

Every hosted Polymarket bot needs revenue, and the structure it picks shapes your costs more than the headline number. Flat percentage: PolyBot documents 1% on successful trades; PolyCop documents 0.5% per executed trade. Odds curve: Kreo documents a formula that scales with how close the price is to 50¢. Subscription hybrids: PolyCopy documents 1% taker / 0.5% maker plus $30/month for real-funds auto-copying. And one terminal, Betmoar, advertises zero platform fees — with the third-party caveat that zero-fee isn’t zero-cost, since spreads still apply to everyone.

How Kreo’s curve works

Kreo’s docs publish the formula: max(0.3%, 7% × price × (1 − price)). The p × (1 − p) term is largest at 50¢ and shrinks toward the extremes, so the fee is highest exactly where contested markets trade and cheapest on near-certainties and longshots.

Plugging in prices:

• At 20¢: 7% × 0.20 × 0.80 = 1.12%
• At 50¢: 7% × 0.50 × 0.50 = 1.75% — the curve’s peak
• At 80¢: 7% × 0.80 × 0.20 = 1.12%
• At 3¢ or 97¢: the formula gives less than 0.3%, so the documented 0.3% floor applies (it binds below roughly 4.5¢ and above 95.5¢)

A $100 trade, three bots, three prices

Two crossover points fall out of the algebra. Kreo’s curve dips below a 1% flat fee only when 7% × p × (1 − p) < 1% — outside roughly the 17¢–83¢ band. Against a 0.5% flat rate the band is wider still: the curve only wins below about 8¢ or above 92¢. Since most contested political, sports, and crypto markets live between 20¢ and 80¢, a curve-fee bot is the more expensive choice for typical trading, and at the 50¢ peak it costs 75% more than a 1% flat competitor.

The flat-fee comparison between the two is simpler: PolyCop’s 0.5% is half of PolyBot’s 1% at every price. That’s a real, documented advantage — our rankings say so plainly — and it sits alongside an equally real trade-off: PolyCop’s custody model is disputed between vendor and third-party accounts, while PolyBot’s Safe-with-key-export design is the clearest documented custody story we verified. Cheapest and most-verified are different axes; the copy-trading comparison scores both.

Subscriptions and the volume break-even

PolyCopy’s automation costs $30/month on top of per-trade fees. Against PolyBot’s no-subscription 1%, the taker rates are identical, so the $30 is strictly additional. The subscription can pay for itself only through PolyCopy’s 0.5% maker rate: saving 0.5% versus a 1% flat competitor requires 0.5% × volume ≥ $30, i.e. $6,000 of maker volume per month just to break even — before valuing any feature differences. For a $500 bankroll doing a few hundred dollars of copies a week, the subscription dominates the fee bill.

Watch for undocumented layers, too. Kreo’s homepage references subscription and performance fees for premium features with the schedule shown only in-bot, and third-party coverage confirms no fixed public tier — pricing opacity we treat as a cost in itself in our methodology.

What fees don’t capture

The cheapest fee can be the most expensive trade. Execution quality (slippage on copied entries), deposit minimums (PolyBot documents $1; PolyCop documents $50 to start copy trading; Kreo documents $2–$7 bridge minimums by chain), sponsored gas (PolyBot, PolyCop, and Kreo all cover Polygon gas), and above all custody risk sit outside the fee line. A percentage point saved per trade buys little if the custody model behind it is an open question — which is why fee score is one-eighth of a tool’s overall rating here, not the headline.