Current implied probability
Up 56%-2.0pt
Market quality
51 / 100
Medium quality24h Volume
$2.5K
Liquidity
$235.5
Low liquidityBid / Ask
54.0% / 57.0%
Spread
3.0 pt
Moderate spreadComments
0
Market data
Updated 8 minutes ago
Sep 18, 26, 12:00 PM UTCSep 21, 26, 8:00 PM UTC
Trends
Related Markets
Related questions for context, not a comparison of equivalent contracts.
Anthropic IPO Closing Market Cap
PolymarketWill Anthropic’s valuation hit __ by December 31?
PolymarketS&P 500 ETF (SPY) Up or Down - Daily
LimitlessDiscord IPO Closing Market Cap
PolymarketWill Anthropic IPO before OpenAI?
Manifold MarketsWill Anthropic stock begin public trading on or before November 6, 2026?
Manifold MarketsRules
This market will resolve to "Up" if the official S&P 500 Index closing price for S&P 500 (SPX) on Monday, September 21, 2026 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day.
- This market will resolve to "Down" if the official S&P 500 Index closing price for S&P 500 (SPX) on Monday, September 21, 2026 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day.
- E.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in which case it would refer to Thursday, or the next most recent trading day.
- If the two specified closing prices are exactly equal, this market will resolve 50-50.
- Note that all figures will be rounded to the nearest cent using standard rounding.
- If SPX does not trade at all during the regular session, the market will resolve 50-50.
Open markets
Exchange
KALSHIBTC price on Sep 20, 2026 at 5pm EDT?
- $77,750 or above98%
- $77,250 or above98%
- $77,500 or above98%
+77 more outcomes
- Total Vol
- $889.9K
- 24h Vol
- $889.4K
POLYMARKETBitcoin above ___ on September 20?
- 68,000100%
- 70,000100%
- 72,000100%
+8 more outcomes
- Total Vol
- $875.6K
KALSHIBTC price on Sep 20, 2026 at 5am EDT?
- $80,000 or above99%
- $71,600 or above99%
- $79,900 or above99%
+97 more outcomes
- Total Vol
- $644.6K
- 24h Vol
- $433.8K
KALSHIBTC price on Sep 25, 2026 at 5pm EDT?
- $73,500 or above+2.0pt98%
- $65,500 or above98%
- $72,500 or above97%
+47 more outcomes
- Total Vol
- $449.4K
- 24h Vol
KALSHIETH price on Sep 20, 2026 at 5pm EDT?
- $2,480 or above98%
- $2,440 or above98%
- $2,400 or above97%
+37 more outcomes
- Total Vol
- $161.9K
- 24h Vol
- $161.4K
LIMITLESSAmazon (AMZN) Up or Down - Daily
- Yes53.5%
- No46.5%
- Total Vol
- $153.3K
- 24h Vol
- $153.2K
- Bitcoin above ___ on September 21?
- Ethereum above ___ on September 20?
- Bitcoin Up or Down on September 20?
- Anthropic IPO by which date?
- Bitcoin price at the end of 2026
- Anthropic IPO Closing Market Cap
- Bitcoin price on September 20?
- How high will BTC get in September?
- ETH price range on Sep 20, 2026 at 5pm EDT?
- Will Anthropic’s valuation hit __ by December 31?
- S&P 500 ETF (SPY) Up or Down - Daily
Frequently asked questions
- What are the current odds for S&P 500 (SPX) Up or Down on September 21??
- Polymarket prices Up at 56% as of September 20, 2026.
- When does S&P 500 (SPX) Up or Down on September 21? resolve?
- S&P 500 (SPX) Up or Down on September 21? is scheduled to resolve on September 21, 2026.
- How is S&P 500 (SPX) Up or Down on September 21? settled?
- Polymarket settles this market as follows: This market will resolve to "Up" if the official S&P 500 Index closing price for S&P 500 (SPX) on Monday, September 21, 2026 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day.