S&P 500 futures stable after Iran-related losses recover

S&P 500 futures regained ground lost due to tensions with Iran, and the Polymarket contract for the S&P 500 opening higher on April 13 sits at 0.1% YES.

Market reaction

The April 13 contract shows 0.1% YES, a near-total rejection of the idea that the S&P 500 opens up. With the ceasefire broken and a naval blockade underway, traders are pricing in continued downside pressure.

Why it matters

Trading volume tells a different story about market depth. The face value is $261,491, but actual USDC traded is only $22,750, a thin market. It takes just $157 to shift the odds by 5 percentage points, meaning even small trades can cause large swings. The biggest single move was an 8-point spike at 1:06 AM, from 8% to 16%, likely one large order rather than a broad shift in sentiment.

What to watch

At 0.1¢, a YES share pays $1 if the S&P 500 opens higher, a 1000x return. A trader would need to believe in a dramatic overnight reversal to justify that bet. Pre-market SPX futures movements, oil price swings, any Jerome Powell statements, and major economic data releases could all shift direction.

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