RizonWhat are 5-minute Bitcoin up/down markets? How they work on Polymarket, Kalshi and others
A market on whether Bitcoin ends a 5-minute block at or above its opening price. How Polymarket, Kalshi, Limitless, predict.fun and OG run them, with fees.
Short answer: A 5-minute Bitcoin up/down market asks one question: will Bitcoin finish this 5-minute block of clock time at or above its price at the start? You buy Up or Down shares priced in cents; the right side pays $1 a share. Polymarket has listed them every five minutes, around the clock, since 12 February 2026; they now settle on a 60-second Chainlink average (TWAP) of BTC/USD, with a taker fee of 1.75¢ a share at 50¢. Kalshi's shortest Bitcoin up/down market is 15 minutes, settled on a 60-second average of CF Benchmarks' index. Limitless, predict.fun and OG also list 5-minute Bitcoin markets.
How a 5-minute window works
- The window opens on the clock. Windows are cut at :00, :05, :10 and so on: Polymarket titles one "Bitcoin Up or Down - October 27, 8:50PM-8:55PM ET". A new one opens the moment the last one closes.
- The price to beat is set at the open. It's Bitcoin's price at the start of the window, from the venue's resolution source. On Polymarket it's the Chainlink TWAP at the start; each window's price to beat is the previous window's final price.
- You trade Up or Down shares. Each share pays $1 if it's right and nothing if it's wrong, so its price in cents reads as a probability: Up at 62¢ costs 62¢ to make 38¢. Prices move all through the window as Bitcoin moves.
- The window closes and settles. The final price is compared with the price to beat. On Polymarket and Kalshi, a final price equal to the price to beat counts as Up.
- Winning shares pay $1 when the market settles, and by then the next window is already trading.
Venue by venue
| Venue | Bitcoin windows | Settles on | Exactly equal | Taker fee at 50¢ | Maker fee |
|---|---|---|---|---|---|
| Polymarket | 5 min, 15 min, 4 h; also hourly and daily | Chainlink BTC/USD 60-second TWAP (hourly and daily: Binance candles) | Up | 1.75¢ a share | None (makers earn rebates) |
| Kalshi | 15 min; hourly and daily price levels | Average of 60 seconds of CF Benchmarks' BRTI | Up ("at least") | $1.75 per 100 contracts | None on this series |
| Limitless | 5 min, 15 min, hourly, daily | Chainlink BTC/USD 60-second TWAP | Up | 2.5% of the trade's value | None |
| predict.fun | 5 min, 15 min, hourly, daily | Chainlink BTC/USDT stream (Binance's mid-price) | 50-50 | Varies; largest at 50¢ or below | None |
| OG | 5 min to weekly, as "Above $X" strikes | A 60-second average of mid-prices (CDNA's U-BTC index) | No: Yes needs strictly above | $0.02 a contract | $0.02 a contract |
Sources: Polymarket's market rules, resolution and fees; Kalshi's market rules and fee schedule; Limitless's resolution and fees; predict.fun's market rules and fees; OG's markets, fees, index rule and launch. All checked on 28 October 2026.
Polymarket's 5-minute markets launched on 12 February 2026 with taker fees on from day one (changelog); its 15-minute markets launched in September 2025 in partnership with Chainlink (Chainlink). In the 24 hours to 01:14 UTC on 28 October 2026, its 5-minute Bitcoin series traded $12.7 million and its 15-minute series $3.3 million (5-minute, 15-minute); in March 2026, GuruFocus reported up to $60 million a day in 5-minute turnover, citing Dune data (via Yahoo Finance).
Kalshi, a US exchange regulated by the CFTC as a designated contract market (Kalshi), lists "BTC price up in next 15 mins?" (series KXBTC15M), with a target price equal to the previous window's final value. It has traded since December 2025. Kalshi pauses trading for maintenance on Thursdays from 3:00 to 5:00 a.m. ET (maintenance).
Limitless runs on Base, and predict.fun on BNB Chain. OG is Crypto.com's prediction market, launched in February 2026, whose contracts are offered through Crypto.com | Derivatives North America, a CFTC-registered exchange.
How the settlement rule changed
Until August 2026, Polymarket settled each window on a single Chainlink price at each end. Researchers then documented large Bitcoin spot orders in the final seconds before settlement, followed by reversals (Dai, Jia and Yu, 2026; CoinDesk). On 7 August 2026 Polymarket switched its crypto up/down markets to Chainlink time-weighted averages, and since 14 August all its 5-minute markets use a 60-second TWAP. Kalshi had already moved its 15-minute markets to 60-second averages in January 2026.
Averaging matters to anyone trading the end of a window: in our data, it halves how often the side ahead 30 seconds before the close ends up losing (the numbers).
What fees cost
Polymarket charges takers fee = shares × 0.07 × p × (1 − p), where p is the price; makers pay nothing. Kalshi's taker fee follows the same curve, rounded up: round up(0.07 × contracts × P × (1 − P)).
| Price (¢) | Polymarket fee per 100 shares ($) | Fee as a share of cost (%) |
|---|---|---|
| 50 | 1.75 | 3.5 |
| 70 | 1.47 | 2.1 |
| 80 | 1.12 | 1.4 |
| 90 | 0.63 | 0.7 |
| 95 | 0.33 | 0.35 |
The fee is largest in dollars at 50¢, around where a new window starts, and as a share of the cost it's largest on cheap shares.
What the format gets right, and what it costs
It's a clean question with a public answer, settled quickly, around the clock. The costs come from the clock:
- Everyone shares the window. Arrive at minute three and you get two minutes, at a price to beat set before you came, with Up or Down already priced away from 50¢. In our data, a random arrival found the side ahead already worth a median 74¢ (the numbers).
- The close is a contest. All positions in a window settle at the same moment, which is what drew strategies built around that moment.
- One market per window. Every five minutes there's a new market, so liquidity is spread across windows rather than sitting in one book.
How Rizon does it differently
Rizon sells the same question without the clock. Every contract is a horizon contract: Bitcoin over 15 seconds, 1 minute or 5 minutes, starting at your fill. The book quotes strikes rather than cents, so the contract you buy is always near the money, and every contract pays a fixed 2×: you pay your size, and get twice it back if Bitcoin finishes on your side of the strike. Exactly at the strike is a push, and both sides get their money back. There are no fees, and it's paper money: $1,000 to start, live prices from Coinbase (API docs).
FAQ
What is a 5-minute Bitcoin up/down market?
A market on whether Bitcoin's price at the end of a 5-minute window is at or above its price at the start. Up and Down shares pay $1 if right and trade in cents, so their prices read as probabilities.
Where can I trade 5-minute Bitcoin markets?
Polymarket, Limitless, predict.fun and OG list 5-minute Bitcoin markets. Kalshi's shortest Bitcoin up/down market is 15 minutes. Rizon offers 15-second, 1-minute and 5-minute horizon contracts with paper money.
How is the result of a Polymarket 5-minute market decided?
By Chainlink's BTC/USD 60-second TWAP: the TWAP at the start of the window sets the price to beat, the TWAP at the end sets the final price, and Up wins if the final price is equal to or greater than the price to beat.
What fees do 5-minute up/down markets charge?
On Polymarket, takers pay shares × 0.07 × p × (1 − p): 1.75¢ a share at 50¢, and makers pay nothing. Kalshi's taker formula is the same, rounded up. Limitless charges takers 5% × (1 − price) of the trade's value; OG charges $0.02 a contract.
What happens if Bitcoin ends exactly at the price to beat?
On Polymarket, Kalshi and Limitless, Up wins. On predict.fun the market resolves 50-50. On OG's strike markets, Yes needs the price strictly above the strike. On Rizon it's a push: both sides get their size back.