There is no system that prints money on a prediction market. There is a way of thinking that separates a price you can read from a trade worth making, and that is what these basics are about.
Strategy here is not a winning system. It is reading a price as a probability, only trading when your honest estimate differs from it by more than the cost of trading, and sizing positions so variance cannot ruin you.
Trading costs eat small edges. A Kalshi taker fee peaks near 1.75 cents on a 50 cent contract (per Kalshi's published fee schedule, effective February 2026, current as of June 2026), and the spread adds more on top.
Most participants do not beat the market after costs. A price is an implied probability, not a prediction, and no strategy removes the risk of loss.
24 June 2026. The concepts here are evergreen, while the fee figures carry an as of June 2026 date.
Sound strategy on a prediction market starts by reading the price as the market implied probability, then asking whether your own honest estimate differs from it by enough to overcome the spread and fees. It treats calibration, being right about probabilities over many trades, as the real skill rather than conviction on any single one, and it sizes each position small enough that an ordinary losing streak cannot end your account. No approach guarantees profit, and most people do not beat the market once costs are counted.
The first useful move in prediction market strategy is to give up the search for a system that wins. There is no sequence of trades, no pattern in the chart, and no tip worth paying for that reliably turns a profit. A prediction market is a competitive marketplace where the price already reflects what a crowd of motivated participants believes, and that price is usually close to right. Most people who trade do not beat the market after the spread and fees are taken out. Beginning from that fact is not pessimism. It is the foundation that makes the rest of this page worth reading.
Once you accept that, strategy becomes a narrower and more honest question. It is not how do I find winners. It is whether a particular price looks wrong by enough to matter, whether the gap survives the cost of trading, and how to arrange your positions so that bad luck, which is guaranteed to arrive, does not wipe you out. Those three ideas, edge, cost, and survival, are the whole of what follows. Everything else is detail.
It also helps to be clear about what a prediction market is not. It is not a slot machine, where the venue profits from a fixed mathematical edge on every spin. A regulated exchange has no house position in the outcome and instead earns from fees and the spread. That means you are trading against other participants, not against a casino, which is why the price is informative and why beating it is hard. Reading that correctly changes how you behave from the first trade onward.
Every yes or no contract on a prediction market settles at a fixed amount, often one dollar, if its outcome happens, and at nothing if it does not. Because of that simple structure, the price of the Yes contract can be read directly as the market implied probability of the event. A contract trading at 60 cents is the market saying, in money, that it puts the chance at about 60 percent. A contract at 12 cents is a roughly 12 percent chance. This is the single most important thing to understand before you trade, because it turns a price into a statement you can agree or disagree with.
Reading the price this way reframes the entire activity. You are no longer asking will this happen. You are asking is 60 percent too high, too low, or about right for this outcome. That is a question you can reason about, gather evidence on, and be measured against later. The Yes and No prices of a fair market roughly add to the settlement amount, so a Yes at 60 cents implies a No around 40 cents, and choosing a side is just choosing which of those two probabilities you think is mispriced.
None of this means the price is a prediction. The market is not promising the event will or will not happen. It is quoting a probability, and probabilities between zero and one are exactly the cases where either result can occur. A 70 percent contract that resolves No was not necessarily wrong. It described a seven in ten chance, and the three in ten happened. Holding that distinction in mind is what keeps a trader honest and is the reason we say repeatedly that prices are not predictions.
A trade is only worth considering when your honest estimate of an outcome sits far enough from the market price that the difference can survive the cost of trading. The strip below shows the idea. The market price is fixed at 60 cents. Where your estimate lands relative to it, and whether the gap clears the cost band around the price, is what decides if there is anything to trade.
Figure 1. Illustration by Prediction Market Index. The cost band stands for the spread plus fees that any round trip must clear. Schematic, not to scale. As of June 2026.
Expected value is the average result of a trade if you could repeat it many times, weighting each outcome by its probability. It is the tool that turns a vague sense that a price looks wrong into a number you can check. For a Yes contract that pays 100 cents on success, bought at a price P cents, using your own probability of success written as a decimal, the gross expected value per contract is your probability times the gain if it wins, minus the chance of losing times the price you paid. The point of the calculation is not precision to the penny. It is to see whether the trade is positive at all once your real estimate, not your hope, goes into it.
Work it through with a market priced at 60 cents. If your honest estimate is 70 percent, the gross expected value is 0.70 times 40 cents of gain, minus 0.30 times the 60 cents at risk, which is 28 minus 18, or about 10 cents per contract before costs. That is a real edge. If instead your estimate is only 62 percent, barely above the price, the gross figure falls to roughly 2 cents, and as the table below shows, the fee alone can erase it. If your estimate equals the price, the expected value before costs is zero, and after costs it is negative. This is why disciplined traders pass on far more markets than they enter.
| Your estimate | Price (Yes) | Gross EV per contract | Approx Kalshi fee | Net EV per contract |
|---|---|---|---|---|
| 70% | 60c | +10.0c | 1.68c | +8.3c |
| 62% | 60c | +2.0c | 1.68c | +0.3c |
| 60% | 60c | 0.0c | 1.68c | about minus 1.7c |
| 55% | 60c | minus 5.0c | 1.68c | about minus 6.7c |
Methodology. Illustrative worked example by Prediction Market Index for a Yes contract that settles at 100 cents. Gross EV uses estimate times 40 cents gain minus one minus estimate times 60 cents at risk. Fee uses the Kalshi taker formula of 7 cents times price times one minus price, which is about 1.68 cents at 60 cents (per Kalshi's published fee schedule, effective February 2026, current as of June 2026). The spread is not included and would reduce net EV further.
Two costs sit between you and any edge. The spread is the gap between the best price to buy and the best price to sell, and you pay roughly half of it on the way in and half on the way out. Fees are charged by the venue on top. On Kalshi the taker fee follows 7 cents times price times one minus price per contract, which is largest in the middle of the range, about 1.75 cents on a 50 cent contract, and smallest near the extremes, a fraction of a penny at 1 cent or 99 cents (per Kalshi's published fee schedule, effective February 2026, current as of June 2026). Other venues price costs differently, which is why we maintain a cross platform fees table you can check before committing.
The lesson from those numbers is that frequent trading on thin edges is a quiet way to lose. Every round trip pays the spread and the fee whether you win or not, so a strategy of placing many marginal trades hands a steady stream of money to costs while your edges, if they exist at all, are too small to outrun them. The participants who last tend to trade rarely and only when the gap between their estimate and the price is wide enough to clear costs with room to spare. Patience is not a personality trait here. It is part of the arithmetic.
Costs also interact with where on the price scale you trade. Because the fee is heaviest near 50 cents, the most uncertain markets are also the most expensive to trade, while high conviction markets near the extremes cost very little to enter. That does not make extreme prices easy money, since a 95 cent contract still loses everything 5 percent of the time, but it does mean the cost structure rewards trading where you genuinely have a view rather than where the action looks most exciting.
The skill that actually pays in prediction markets is calibration, which means your stated probabilities match how often things really happen. If you are well calibrated, the outcomes you call 70 percent likely occur about 70 percent of the time, the ones you call 30 percent occur about 30 percent of the time, and so on across the range. Calibration is not the same as being confident, and it is not the same as being right on any single market. A loud, certain forecast that is poorly calibrated loses money over time, while a modest, accurate one can make it.
The chart below shows what good calibration looks like. The straight line is perfect calibration, where predicted probability equals observed frequency. A trader who plots their own forecasts against what later happened, and lands near that line, has a genuine and rare ability. Most people, including most experts, are overconfident, meaning their high probabilities come true less often than they claimed. You can only see this over a sample of many resolved markets, never from one trade, which is why keeping an honest record of your forecasts and their outcomes is the most useful habit in this whole field.
Figure 2. Illustration by Prediction Market Index. A schematic calibration chart, not real data. The dashed line is perfect calibration; hollow points show the common pattern of overconfidence at high predicted probabilities.
Even a real edge plays out through noise. If you have a genuine advantage and call a string of 70 percent outcomes, roughly three in ten will still resolve against you, and they can cluster into a losing streak that feels like proof you were wrong. Variance, the normal swing of luck around the average, is not a sign of failure. It is the texture of probability. The job of position sizing is to make sure that an ordinary and fully expected run of losses does not take your account with it.
The common principle, and this is general information rather than advice, is to risk only a small fraction of your total bankroll on any single market. Keeping each position small means no one resolution can do lasting damage, and it lets your edge, if you have one, show up over many trades rather than be erased by a single bad cluster. The exact fraction is a personal choice tied to how much you can comfortably afford to lose, but the direction is clear. Smaller and steadier survives where large and concentrated does not.
Two related habits matter as much as the size of each bet. The first is to never add to a position to chase a loss, since doubling down to get even is how a manageable loss becomes an unmanageable one. The second is to set the amount you are willing to lose before you start and to treat it as fixed, never funded by borrowing and never topped up in the heat of a bad day. These are not exciting rules. They are the ones that decide who is still trading a year from now.
A surprising number of losses come not from a bad probability but from misreading what the contract says. Every market has resolution rules that define exactly which outcome pays, the source that will be used to settle it, and the date by which it resolves. Two markets that look like the same question can settle on different sources or different cut off times, and a contract that seems to match your view can in fact turn on a technicality you did not notice. Before you trade, read the rules the way you would read the fine print on a contract, because that is what it is.
Pay particular attention to the settlement source and the timing. If a market resolves on a specific official report released at a specific time, then news that arrives before the official figure may move the price without changing the eventual settlement, and the reverse can also happen. Knowing where the truth will come from, and when, is part of having a real view rather than a vague one. Our guides on how event contracts settle and on market resolution dates go into this in more depth, and they are worth reading before you put money on anything time sensitive.
None of this requires complicated tools. A workable routine is to write down your own probability for an outcome before you look hard at the price, so the price does not anchor you. Then compare the two. If your estimate and the price are close, there is nothing to do, and doing nothing is a position. If the gap is wide, ask whether it survives the spread and the fee using the kind of expected value check in Table 1, and ask honestly why you would know something the market does not. If you cannot answer that last question, the gap is more likely your error than the market's.
If a trade clears those tests, size it small, note the resolution rules and the date, and record the forecast you made so you can check your calibration later. After it resolves, write down what happened and whether your probability was reasonable, win or lose. Over months, that record is the only honest scoreboard you have, and it will teach you more than any guide, this one included. Strategy in prediction markets is finally just this loop, done patiently and without ego, far more often passing than trading.
And keep the frame in view throughout. A price is an implied probability, not a promise. The venue is not your opponent and not your friend. You can be right about a probability and still lose a given trade, and you can be wrong and still win one. The discipline is to judge yourself on the quality of your probabilities and your risk control over a long sample, not on the result of the last market you traded. That is the difference between gambling on events and reasoning about them.
No strategy removes the risk of loss, and most participants do not beat the market after costs. This page is general information, not advice, and does not tip outcomes. Stake only what you can afford to lose, never to chase a loss, and never on borrowed money. If trading stops feeling like a choice, that is the moment to step back. You must be 18 plus or the legal age in your region. In the United States you can call or text the helpline on 1-800-GAMBLER or visit ncpgambling.org.
The concepts on this page connect to the rest of the reference. The expected value guide works the arithmetic in more detail, the position sizing and bankroll guide covers survival, and the cross platform fees table shows what each venue actually charges so you can judge the cost band for yourself. We do not place an open account link here, because the right venue depends on where you are and what you can legally use. Start with the facts, then decide.
No strategy guarantees a profit, and most participants do not beat the market after fees and the spread. The useful question is not how to pick winners but whether a price looks wrong by enough to matter once costs are taken out, and how to size and limit positions so a normal losing run does not ruin you.
Edge is the gap between your honest estimate of an outcome and the price the market is charging for it. A Yes contract at 60 cents implies a 60 percent chance. If your well reasoned estimate is meaningfully higher or lower than that, and the gap is bigger than the cost of trading, you have a possible edge. If your estimate matches the price, there is no edge to trade.
Fees and the spread come out of every round trip and quietly erode small edges. On Kalshi, for example, the taker fee follows 7 cents times price times one minus price per contract, which peaks at about 1.75 cents on a 50 cent contract (per Kalshi's published fee schedule, effective February 2026, current as of June 2026). A two cent gross edge can vanish entirely once that cost is paid, so frequent trading on thin edges is usually a losing approach.
Calibration is whether your stated probabilities match reality over many forecasts, so that the things you call 70 percent likely happen about 70 percent of the time. It matters more than conviction, because a confident wrong probability loses money while a modest accurate one can make it. You can only judge calibration over a sample of outcomes, not a single trade.
There is no universal number, and this is general information rather than advice. The common principle is to keep any single position small relative to the total you can afford to lose, so that variance, which means normal swings of luck, cannot wipe you out during a losing streak that is statistically expected even when you have an edge. Many careful participants risk only a small fraction of their bankroll on any one market.
Copying trades is not a strategy, because you inherit someone else's entry price, timing, and risk tolerance without their reasoning or their exit plan. By the time a position is visible or widely discussed, the price has usually already moved. It is more durable to understand why a price might be wrong yourself, and to accept that often it is not wrong at all.
Reviewed by Fredrik Filipsson, Editor, on 24 June 2026. The reasoning here is evergreen; the fee figures carry an as of June 2026 date and are checked on the regular review cycle.