15-minute BTC FAQ
1.What am I actually buying — is this Bitcoin?
You are buying a contract on an outcome, not Bitcoin. A winning contract pays $1, and a losing contract pays $0.
2.What does “Up” mean exactly? How is the winner decided?
Polymarket compares the market’s closing value with its opening value. If the close is equal to or higher than the open, Up wins; if it is lower, Down wins.
3.What is the “price to beat”?
It is the market’s official opening value. Polymarket calculates it by averaging 60 BRTI readings from the minute before the 15-minute window starts.
4.The price was above the line at the end — why did I lose?
The last dot on the chart does not decide the winner. Polymarket averages 60 BRTI readings from the final minute, so that average can be below the price to beat even if the last visible price is above it.
5.What happens if it’s an exact tie?
Up wins. The rule says the closing value must be equal to or higher than the opening value.
6.Where does the price come from? What is BRTI?
BRTI is the CME CF Bitcoin Real Time Index, a Bitcoin price benchmark published once per second. Polymarket uses this index for settlement, not the price shown by one exchange.
7.Can one exchange going crazy swing the result?
Not by itself. BRTI combines price data from several exchanges, which reduces the effect of one unusual exchange price.
8.Why does the chart look different from the buy/sell prices?
The chart tracks Bitcoin’s reference price. The Up and Down prices are contract prices set by buyers and sellers, so they can move before the chart redraws or move for different reasons.
9.What does 63¢ mean? Is that the chance of winning?
It means one contract costs 63¢ at that moment and pays $1 if it wins. People often read 63¢ as the market suggesting about a 63% chance, but it is only a market price—not a guarantee.
10.Why didn’t my order fill even though the price hit my number?
A limit order fills only when another trader matches it, and other orders may be ahead of yours. The Bitcoin chart touching a number does not fill a contract order, and a briefly shown contract price may not have enough contracts available for everyone.
11.Can I sell before the 15 minutes are up?
Yes, while trading is still open. Your sale fills only if a buyer matches your price, so the amount you receive is not guaranteed.
12.Why do the Up and Down prices sometimes add up to more than $1?
The displayed buy prices may be the lowest prices that two different sellers will accept. Buying both means crossing both bid-ask spreads, so those two prices can total more than $1.
13.Why does the price jump around so fast — are bots doing that?
Often, yes. Bots and people can quickly place, change, or cancel orders as Bitcoin moves and time runs out, so the contract price can jump in seconds.
14.Are there fees?
Yes. An order that trades right away usually pays a taker fee, while an order resting on the book can earn a maker rebate; the amount depends on the contract price and size.