Some links on this page are affiliate links: if you buy through them we may earn a commission, at no extra cost to you.
The cheapest advertised fee is rarely the cheapest trade. Evaluate a prediction market by calculating the all-in cost at your actual order size, checking the bid-ask depth you can really execute against, and reading the settlement rule that determines whether your position pays. A market with a nominally low fee can still cost more if its spread is wide, its order book is shallow, or its resolution source leaves room for disputes.
The practical method is to record the maker or taker status, contract price, fee formula, rebates, funding charges, executable spread, depth, expected slippage, resolution source, cutoff time, edge cases, payout rule and dispute process. The examples below use official venue terms documented in 2026; fee schedules and incentive programs can change, so verify the live rule pages immediately before trading.
As an Amazon Associate I earn from qualifying purchases.
Quick wins for a faster PC:
Scan for outdated or missing drivers - takes under a minuteDriver Scan →Repair Windows errors before they cause bigger problemsFix Now →At a glance
| Name | Best for | Key fee or settlement fact | Checked |
|---|---|---|---|
| Kalshi | Comparing a documented maker/taker schedule and fixed-dollar yes/no settlement | General fee formula uses 0.07; maker formula uses 0.0175; no settlement fee for simple yes/no contracts in the cited schedule | Oct 2026 |
| Polymarket | Markets where category-specific taker rates, zero maker fees and oracle rules are acceptable | Taker rates range from 0 to 0.07 by category; makers pay zero trading fee; winning tokens redeem for $1 | Oct 2026 |
This is a framework, not a claim that either venue is always more liquid or less expensive. Costs and execution quality vary by event, category, time and order size.
What should you compare before looking at a quoted price?
Start with contract equivalence, then compare execution. Two contracts that appear to ask the same question are not comparable until their resolution source, end date, cutoff time, edge-case treatment and payout conditions match.
Popular on Amazon
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
- Write the exact event. Copy the outcome wording, date, time zone and any “by,” “at,” or “before” condition.
- Identify the resolution source. Note the named data provider, official announcement or oracle and whether a secondary source can be used.
- Classify the order. A trade that immediately matches resting liquidity is a taker execution; an order that rests and is later filled is generally maker execution, subject to the venue’s definitions.
- Measure executable prices. Record the best bid, best ask, quantities at each level and the average fill for your intended size.
- Calculate the payout and every charge. Include trading fees, rebates, deposits, withdrawals, clearing, settlement, network or other funding costs when the venue documents them.
- Read the failure rules. Check cancellations, postponements, ties, partial outcomes, missing data, disputes and expected settlement timing.
How much do prediction markets charge?
Fees depend on who supplies liquidity, the contract price, the number of contracts and the market category. A headline percentage is incomplete because the price term p × (1-p) makes the charge largest near a 50-cent contract and smaller near 0 or $1.
Maker versus taker fees
A taker removes an existing bid or ask and normally pays for immediate execution. A maker posts a resting order; the venue may charge a lower fee, charge nothing, or pay a rebate. Confirm the classification for the specific order type rather than assuming that a limit order is always a maker order.
Free tools Windows power users keep installed
One-click scans. No signup required.
Kalshi’s documented formulas
Kalshi’s fee schedule, updated and effective July 7, 2026, gives a general formula of round up(M × 0.07 × C × P × (1-P)) for applicable immediately matched orders. It separately documents a maker formula of round up(M × 0.0175 × C × P × (1-P)); the multiplier can depend on the contract. The schedule states that simple yes/no markets have no settlement fee. It also notes that sub-cent scalar settlement can receive different treatment.
In those formulas, use the venue’s definitions for the contract multiplier M, contract count C and price P. Do not substitute a different multiplier or round the result yourself when the contract page specifies another one.
Polymarket’s category rates
Polymarket documents the taker formula C × feeRate × p × (1-p). Makers pay zero trading fee under the cited documentation. The documented taker rates are: Crypto 0.07; Sports 0.05; Finance 0.04; Politics 0.04; Economics 0.05; Culture 0.05; Weather 0.05; Other/General 0.05; Mentions 0.04; Tech 0.04; Geopolitics 0; and Combos 0.05.
Those rates describe gross trading fees. Polymarket also documents maker rebates and a taker-rebate program, so the eventual net cost can differ from the amount charged at execution. A zero-rate category still needs a check for funding or other charges not included in the trading-fee formula.
Also popular on Amazon
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Worked examples at the same trade size
The following calculations are illustrative, using 100 contracts priced at $0.60, so the pre-fee trade value is $60 and the maximum gross payout is $100. Kalshi’s example assumes a contract multiplier of 1; the applicable contract page controls.
| Venue and category | Execution | Entry price and contracts | Formula and fee | Gross fee as trade value | Gross fee as maximum payout | Rebates or other charges |
|---|---|---|---|---|---|---|
| Kalshi, general schedule | Immediately matched (taker) | $0.60 × 100 | 1 × 0.07 × 100 × 0.60 × 0.40 = $1.68, rounded up under the schedule |
2.80% | 1.68% | No settlement fee stated for simple yes/no; funding or withdrawal charges not stated in the cited schedule |
| Kalshi, maker formula | Maker execution | $0.60 × 100 | 1 × 0.0175 × 100 × 0.60 × 0.40 = $0.42, rounded up under the schedule |
0.70% | 0.42% | Multiplier and eligibility can vary by contract; verify the market schedule |
| Polymarket, Crypto | Taker | $0.60 × 100 | 100 × 0.07 × 0.60 × 0.40 = $1.68 |
2.80% | 1.68% | Makers pay zero trading fee; documented rebates may change net cost |
| Polymarket, Sports | Taker | $0.60 × 100 | 100 × 0.05 × 0.60 × 0.40 = $1.20 |
2.00% | 1.20% | Category rate is 0.05; rebates and any non-trading charges must be checked separately |
| Polymarket, Geopolitics | Taker | $0.60 × 100 | 100 × 0 × 0.60 × 0.40 = $0 gross trading fee |
0% | 0% | Zero documented taker rate does not establish that deposits, withdrawals or other costs are zero |
The same rate produces a different dollar charge at a different price. At 50 cents, the price term is 0.25; at 90 cents it is 0.09. Always recalculate with the actual entry price and contract count rather than applying a flat percentage to the notional.
How do rebates, referrals and funding charges affect the all-in cost?
Separate the amount charged when the order fills from money that might be returned later. A rebate is valuable only if the order qualifies, the program remains active and the payment arrives under its stated conditions.
- Maker rebates: Polymarket documents maker rebates. Record the gross taker fee or zero maker fee first, then apply only the rebate rate and eligibility published for that market and period.
- Taker rebates: A taker-rebate program can reduce net cost, but it should not be treated as an automatic discount. Check whether the market, account and volume qualify.
- Referral rewards: Polymarket’s updated referral terms took effect May 28, 2026. The documented program requires $10,000 in lifetime trading volume to earn rewards, attributes a signup when it occurs within 30 days of a click, pays 10% of net trading fees from a direct referral or 5% from an indirect referral, and pays rewards daily in pUSD. Rewards end when the referral reaches Platinum or 30 days elapse, whichever comes first; free markets do not generate referral rewards. The terms can change without notice, so this is not a universal fee reduction.
- Funding and cash movement: Record deposit, withdrawal, clearing, network and settlement charges when the venue states them. If a charge is not stated in the cited documentation, mark it “not stated” and verify it before committing funds rather than assuming it is free.
For a useful worksheet, calculate both percentages: all-in cost ÷ amount paid and all-in cost ÷ maximum payout. The first shows how much the trade price is being burdened; the second shows the fee against the dollar that can be redeemed if the outcome wins.
Recommended Free Tools
What is the spread, and how much liquidity is actually available?
The spread is the best ask minus the best bid. The ask is what a buyer pays for an immediate fill; the bid is what a seller receives. A displayed midpoint is only an estimate and can be untradeable when the spread is wide.
Measure relative spread, not just cents
Report the absolute spread in cents and the relative spread as (best ask − best bid) ÷ midpoint × 100. A two-cent spread is material for a 20-cent contract but relatively small for a 90-cent contract. Keep the timestamp because the book can change between observation and order entry.
Also popular on Amazon
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Walk the order book for your intended size
Polymarket describes a central limit order book in which supply and demand form prices. Its documentation says the displayed price is generally the midpoint, but a wide spread can cause the last traded price to be displayed instead. Therefore, use the ask for an immediate buy and the bid for an immediate sale, not the headline number.
Use this worksheet for every proposed trade:
| Field | What to record | Why it matters |
|---|---|---|
| Best bid / best ask | Price and timestamp | Defines the executable top of book |
| Absolute spread | Ask minus bid, in cents | Direct crossing cost before trading fees |
| Relative spread | Spread divided by midpoint | Makes markets at different price levels comparable |
| Top-level quantity | Contracts available at the best bid and ask | Shows whether your order fits without moving levels |
| Cumulative depth | Quantity within 1, 2 and 5 cents of the best price | Shows how far the book can absorb a larger order |
| Average executable price | Weighted average after consuming levels | Reveals actual slippage for your size |
| Resting or immediate | Whether the order would execute now or wait | Changes maker/taker treatment and fill risk |
| Book stability | Several snapshots over a stated interval | Distinguishes replenishing depth from a fleeting quote |
Worked slippage example
Suppose an illustrative book shows an ask of $0.61 for 40 contracts and $0.62 for the next 60. Buying 100 contracts requires walking both levels: (40 × $0.61 + 60 × $0.62) ÷ 100 = $0.616 average fill. If the midpoint was $0.600, the order’s price slippage is 1.6 cents per contract, before trading fees. This example is a calculation method, not a live market observation.
Repeat the walk for 500 or 1,000 contracts if that is your planned size. Compare the weighted average with the midpoint estimate and report the difference. A market can display substantial historical volume yet have a thin current book; conversely, modest volume can still provide adequate two-sided depth for a small order.
Volume is useful context, not a complete liquidity score. Continuous bids and asks can deepen the book, narrow spreads, improve price discovery and absorb flow, but the relevant question is whether that depth exists at the moment and size of your order.
Which settlement rules determine whether a position wins?
Settlement rules are part of the product, not fine print. Capture the exact outcome wording, resolution authority, timing and dispute path before comparing prices or calling two contracts equivalent.
Kalshi’s yes/no settlement mechanics
Kalshi’s documentation says a Yes outcome pays Yes holders $1 per contract and a No outcome pays No holders $1 per contract; only net positions settle. Markets generally settle shortly after expiration, but timing can vary with the market type, data availability and manual review. Simple yes/no settlement fees are stated as zero, while sub-cent scalar settlement can involve different treatment.
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsAlso popular on Amazon
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Widely Compatible: Transform any USB-C port into a USB-A port and USB-A port into a USB-C port, and connect up a wide range of USB-C(including MacBook, iPad Pro/Air/Mini, iPhone models with USB C ports, Samsung Galaxy series, and Google Pixel series. ) and USB A devices(including external hard drives, phones, mice, printers, and more)
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Record the expiration moment and the earliest eligible resolution time separately. “Settles shortly after expiration” is not a promise of an identical clock time for every market.
Polymarket’s oracle and token payout
Polymarket states that winning tokens redeem for $1 each and losing tokens become worthless. Its prediction markets use UMA’s Optimistic Oracle; up-down markets use a Chainlink time-weighted average price. Each market’s rules identify the resolution source, end date and edge cases.
A proposal normally requires a bond followed by a challenge period. The documented typical UMA proposal bond is about $750, the challenge period is two hours, and an escalation can lead to an approximately 48-hour UMA vote. These are mechanics of the stated process, not a guarantee that every market resolves on the same schedule.
The key rule is explicit: the market title describes the question, but the rules define how it resolves. Read the rule text for cancellations, postponements, ties, partial outcomes, missing data and any alternative source that can be used if the primary source is unavailable.
Settlement checklist
- Outcome wording: Copy the exact Yes and No conditions, including thresholds and units.
- Resolution source: Identify the primary source, oracle or index and what happens if it is unavailable.
- End date and cutoff: Record the time zone, the event end and the earliest time a result can be determined.
- Edge cases: Check cancellation, postponement, tie, partial completion, revisions and missing-data clauses.
- Authority: Note who may propose a result, who may challenge it and whether an escalation body can override it.
- Bond and challenge window: Record the required bond, challenge duration and escalation route.
- Payout: Confirm the redemption amount, whether losing positions expire worthless and whether positions are netted.
- Timing: Distinguish the event’s end from actual settlement and allow for manual review or an oracle vote.
What happens if the result is disputed?
A dispute does not necessarily mean the market is invalid; it means the published resolution process has to run. The financial and timing consequences depend on the venue’s rule hierarchy, bond requirements and escalation mechanism.
For a market using an optimistic process, first identify the proposed answer and the challenge window. If challenged, determine whether another proposal is allowed, whether a larger governing vote is triggered and how long that stage normally takes. Do not treat an early proposal as final until the rules say the result is settled and redeemable.
Also popular on Amazon
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
When comparing venues, a clear primary source with a defined fallback can be more valuable than a lower trading fee. A contract whose source can be revised, interpreted differently or delayed should carry a larger uncertainty allowance in the decision, even when its displayed price looks attractive.
How do you compare two markets that appear to ask the same question?
Use a side-by-side record and reject the comparison if any material rule differs. A price gap is not an arbitrage signal when one contract uses a different cutoff, source, threshold or cancellation rule.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
| Comparison item | Market A | Market B | Pass condition |
|---|---|---|---|
| Exact outcome wording | Copy verbatim | Copy verbatim | Same event and threshold |
| Resolution source | Named source or oracle | Named source or oracle | Equivalent authority and fallback |
| End date and time zone | Timestamp | Timestamp | Same cutoff or an explicitly valued difference |
| Edge cases | Cancellations, ties, missing data | Cancellations, ties, missing data | No hidden rule changes the payoff |
| Bid, ask and depth | Timestamped snapshot | Timestamped snapshot | Enough two-sided depth for the planned size |
| All-in cost | Fee plus spread, slippage and other charges | Fee plus spread, slippage and other charges | Compare net cost, not headline fee |
| Settlement timing | Expected window and review risk | Expected window and review risk | Acceptable delay and dispute process |
Which market is the better choice for a particular order?
Choose the market that minimizes all-in cost for your actual order while providing executable depth and an unambiguous settlement rule. There is no defensible venue-wide “most liquid” ranking from the available evidence because liquidity changes by event, category, time and size.
- Filter for rule equivalence. Remove any contract whose source, cutoff or edge cases do not match the question you intend to trade.
- Estimate the fill. Walk the bid or ask for your size and include the spread and slippage.
- Add trading fees. Apply the correct maker or taker formula, category rate and contract multiplier.
- Apply only certain rebates. Count a rebate only when its eligibility and payment terms are established; otherwise show the gross cost.
- Check cash and settlement costs. Include documented funding, withdrawal, clearing or settlement charges and mark unknowns for verification.
- Value timing and disputes. Prefer the rule set whose resolution source, challenge window and expected settlement delay fit your risk tolerance.
- Recheck immediately before submitting. Fees, rebates and referral terms can change, and the order book can move after the worksheet was completed.
What should you record in a before-you-trade worksheet?
A short record makes the comparison auditable and prevents a midpoint or headline fee from becoming the decision by accident.
- Venue, market name and category
- Exact outcome wording, source, end date, cutoff time and time zone
- Contract count, entry price and maximum payout
- Maker or taker status and the formula used
- Gross trading fee, rebate assumption and net fee
- Best bid, best ask, spread, midpoint and timestamp
- Quantity at the top level and cumulative depth within 1, 2 and 5 cents
- Weighted average fill and estimated slippage for the planned size
- Deposit, withdrawal, clearing, settlement or network charges, if stated
- Cancellation, postponement, tie, missing-data and dispute rules
- Expected settlement window and possibility of manual or oracle review
- Date the fee and rule pages were checked
Frequently Asked Questions
Can a $1 prediction-market contract lose more than $1?
The documented payout is generally capped at the contract’s stated redemption amount, but your total cash outlay can include the purchase price, trading fee, spread, slippage and any separately documented funding charge. Calculate the maximum payout and the full amount paid before entering, rather than treating the face value as your break-even price.
How often should I refresh an order-book liquidity check?
Refresh it whenever the market is fast-moving, your order is large relative to displayed depth, or several minutes have passed since the snapshot. Keep the timestamp and, for meaningful trades, compare multiple snapshots so a one-time quote is not mistaken for stable liquidity.
The Tool Desk
Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Does a wider spread always mean a bad market?
Not necessarily. A wide spread may be reasonable for a difficult-to-price event or an early market, but it raises the cost of an immediate fill and signals that a larger order may move through several price levels. Compare the spread with your size, the available depth and the certainty of the settlement rule.
What should I do if the event result is revised after publication?
Follow the market’s stated resolution hierarchy rather than an informal news report. Check whether the rules permit a revised source, a reopened proposal or a challenge, and wait for the venue’s final settlement status before assuming tokens or contracts are redeemable.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
