S&P 500, NASDAQ near record closes on US-Iran peace deal optimism

The S&P 500 and Nasdaq are approaching record closes in the final hour of trading, driven by optimism around a potential U.S.-Iran peace deal. The S&P 500 opening higher on April 16 is priced at 99.9% YES on Polymarket.

Traders are pricing in a continuation of the rally after President Trump stated that the “Iran war is very close to being over.” The April 16 market shows strong confidence in a positive open, with pre-market futures pointing green. A 12-point spike at 12:31 PM moved the contract from 74% to 87% YES.

Volume on the April 16 market sits at $65,683 in USDC traded over the past 24 hours. That level of liquidity means traders are putting real money behind the directional bet, not just watching. The 12-point spike was the largest single price move, likely triggered by large orders reacting to the Iran news.

The optimism traces directly to diplomatic progress on Iran, a concrete catalyst rather than speculative earnings chatter. With April 16 just hours away, buying an up open at 99.9¢ offers almost no upside. The contrarian play here is betting on an unexpected overnight shock, but you’d need something genuinely out of left field to move this.

Watch overnight futures and any last-minute statements from Jerome Powell or other Fed officials. A surprise comment could shift expectations before the opening bell.

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