Kalshi vs Polymarket: fees, rules and access compared

Kalshi vs Polymarket at a glance

Polymarket is not one interchangeable product

Kalshi’s member agreement names KalshiEX, LLC. Polymarket international’s terms name Adventure One QSS, Inc. The Polymarket US exchange is a separate product associated with QCX LLC. A feature, fee or contract on the international product does not establish the same feature, fee or contract on the US product.

The international terms prohibit US persons from trading on that product. Check current US eligibility with each operator before signing up.

Compare the actual fee, not a slogan

Kalshi documents market-dependent fees, including fees on some maker orders. Polymarket international also documents market-dependent taker fees. A universal “no fees” claim would erase those differences.

Polymarket US publishes category-dependent, price-weighted fees. Its combined-contract documentation currently conflicts, so an exact combined-contract rate is not presented. No international fee is substituted for the US schedule. Fees, spread and available depth must all be known before a lowest-price comparison is complete.

The rules can change the comparison

Kalshi describes settlement by the written contract rules and source agency. Polymarket international describes a proposal and dispute process using UMA. The exact contract still determines its resolution conditions.

Before prices are compared, match the underlying event, outcome, threshold, timeframe, resolution source and material cancellation terms. If a material condition differs, show the contracts as related rather than equivalent.

What the comparison covers

This comparison explains documented product differences. Eligibility depends on the exact product and location; transaction costs depend on the order. Check the product’s current terms before relying on either. No sign-up offer or execution-quality ranking is included.

Use this comparison in three passes

First identify the product: Kalshi, Polymarket international and Polymarket US have distinct source records. Next compare the contract definition and resolution process. Finally inspect the applicable costs and account terms for the exact product.

A similarity at one stage does not answer the next. Matching topics do not establish matching contracts, and matching contract questions do not establish identical transaction costs. The linked reviews provide the product-level context behind this overview.

Sources and citation

1. Kalshi member agreement: KalshiEX, LLC
2. Kalshi: fees
3. Kalshi: market FAQs and settlement
4. Polymarket international terms
5. Polymarket: transparency and separate products
6. Polymarket US fee schedule
7. Polymarket US exchange
8. Polymarket international: fees
9. Polymarket international: resolution

PlayPicks analysis is original synthesis. Linked provider documents remain the primary source for their own contract terms.