I’ve traded on both for about a year now, so here’s the version that skips the marketing comparison tables. The short version: they’re not interchangeable, and which one you can even use often gets decided for you by where you live.
The fee structures aren’t even measured the same way. A standard sportsbook prices in roughly 5.3% margin on a typical two-way line (1.95/1.85 odds). Kalshi charges per contract instead — a cent or two depending on price, no flat percentage. The terminal I use on Polymarket’s liquidity charges a flat 1% of volume. Three different units, which makes “which is cheaper” depend entirely on how you trade, not just which platform you pick.
Kalshi vs Polymarket: the structural difference
Kalshi is a CFTC-regulated Designated Contract Market — a federally regulated exchange, which is exactly why it’s legal in states like Texas where traditional sportsbooks aren’t. Polymarket isn’t CFTC-registered the same way, which is part of why its US access situation is closer to “restricted” than Kalshi’s “regulated and open.”
That regulatory gap shows up in practice as two different products with overlapping goals. Kalshi’s federal registration means it can operate openly across most US states without the geoblocking Polymarket applies. Polymarket’s advantage runs the other direction — deeper liquidity specifically in sports and esports categories, built up over a longer operating history in that niche, even without the same US regulatory clearance.
Kalshi fees: not a percentage, a per-contract charge
Kalshi fees run roughly $0.01–$0.02 per contract depending on where the price sits, and the charge doesn’t change by which state you’re trading from. For high-volume, low-price trades this adds up differently than a percentage-of-volume model — worth actually running the math for your own trading pattern rather than assuming one fee structure is universally cheaper.
Kalshi vs Polymarket comparison: the number that actually matters
Run your own trade volume through both fee structures before picking one — a cents-per-contract model and a percentage-of-volume model cross over at different points depending on contract price and size. There’s no single answer that holds for every trader; the comparison only means something once you plug in your own numbers.
Robinhood prediction markets: the newest entrant
Robinhood has moved into event contracts too, layering prediction markets onto an app most people already have for stocks. It’s worth knowing about as a comparison point — one more sign this category isn’t a niche experiment anymore, it’s attracting mainstream brokerages, not just crypto-native platforms.
Best prediction markets: there isn’t one universal answer
“Best” depends entirely on what you’re optimizing for. Regulatory clarity in the US points toward Kalshi. Sports and esports market depth is where a terminal built on Polymarket’s liquidity — like the one I use — tends to have the edge, since that’s specifically what it’s built around rather than being one category among many alongside politics, economics, and culture.
Anyone answering “which is best” without asking what you’re trading is skipping the part of the question that actually determines the answer.
Best prediction market app: judged by what, exactly
An app being polished doesn’t tell you about liquidity depth in the specific category you actually trade. A clean interface with a thin order book in your market of interest is worse than a rougher one with real volume behind it — check the book before judging the app.
Prediction market apps: the crowded field, and the best prediction market apps right now
DraftKings prediction markets: sportsbooks entering from the other side
DraftKings, a sportsbook by origin, has been moving into prediction-market-style contracts too — the reverse direction from Kalshi and Polymarket, which started as exchanges and are picking up sports coverage. Worth watching which direction the category consolidates toward.
Polymarket competitors: the honest list
Kalshi is the most-discussed. Robinhood and DraftKings are newer entrants approaching from different starting points — a brokerage and a sportsbook respectively. None of them are identical products; they’re solving overlapping but not identical problems, and lumping them together in one “best of” list obscures more than it explains.
Picking between them isn’t really about finding “the winner” — it’s about matching the regulatory situation and category depth to what you’re actually trying to trade. Someone focused on US election markets has different priorities than someone focused on NFL game outcomes, and the right platform for one isn’t automatically right for the other.
Kalshi alternative: when Polymarket-based access makes more sense
If Kalshi doesn’t cover a market you want, or you’re outside its accessible regions, a terminal on Polymarket’s liquidity is the alternative — specifically strong on sports and esports coverage rather than the broader mixed-category approach Kalshi takes.
Canada: Kalshi arrived first, via Wealthsimple — with sports carved out
Canada’s situation is easy to get wrong. Wealthsimple, a major Canadian brokerage, got regulatory approval to offer event contracts to Canadian users — but sports was explicitly excluded from that approval. That’s the detail most coverage skips: Canadians can access some Kalshi-style event contracts through Wealthsimple, just not sports ones.
For sports specifically, that gap is exactly what a sports-focused terminal fills. It’s a distinction worth being precise about, because a Canadian reader searching “Kalshi Canada” is likely to land on coverage that talks about event contracts generally without mentioning that the one category they probably care about — sports — isn’t part of what’s currently permitted through that specific channel.
How I actually trade
Access — wallet created automatically, no separate signup form.
Deposit — USDT, network fee shown as its own line.
Pick a sports or esports market on the live board.
Trade — contract price set by the order book, flat 1% fee shown before confirming.
overdog.bet is what I use for sports and esports specifically. My trade history sits on the proof page — public.
FAQ
Is Kalshi legal in Texas? Yes — Kalshi is a CFTC-regulated federal exchange, which puts it outside Texas gambling law entirely, unlike a state-licensed sportsbook.
Is Kalshi legal? Legal federally as a CFTC-regulated exchange, available in most US states. A handful of states have pushed back on specific contract categories, so availability isn’t perfectly uniform everywhere.
Is Kalshi legal in Canada? Not directly as Kalshi — but Wealthsimple offers similar event contracts under its own regulatory approval, with sports specifically excluded from what’s currently permitted.
Responsible gambling isn’t a line to skip. If trading stops being a deliberate decision and starts being a way to cover a budget gap, that’s a reason to pause, not size up.
Kalshi vs Polymarket 2026: Fees, Liquidity, Legality and Which You Can Actually Use was originally published in Coinmonks on Medium, where people are continuing the conversation by highlighting and responding to this story.