In short: on Thursday, November 5, 2026, the Nasdaq Composite fell 5.52% to 24,315.00 — its worst day since the April 2025 tariff shock. The Nasdaq 100 lost 6.36%, erasing roughly $2.5 trillion in market value by Reuters’ count. The trigger: fears that, after the US midterm elections, the build-out of AI data centres will slow down.

What happened on the stock market on November 5?

  • Nasdaq Composite: −5.52%.

  • Nasdaq 100: −6.36%.

  • S&P 500: −4.4%, its worst day since April 2025.

  • Dow Jones: −1,833 points (−3.44%) to 51,523.

  • PHLX Semiconductor Index: −12.25%.

Companies tied to AI infrastructure were hit hardest: AMD and Micron fell about 17%, Nvidia 9.26% and cloud provider CoreWeave nearly 10%. The hyperscalers held up better, with Amazon and Alphabet down 2.2% each.

Why did the US elections hit AI stocks?

In the November 3 midterms, Democrats won races including in key data-centre states, and NBC News reported that many winning candidates had pledged to slow or halt data-centre construction. In local ballot measures, the side favouring restrictions won 38 of 39 fully counted data-centre votes. Markets read this as a sign that new AI capacity could arrive more slowly and at a higher cost — meaning fewer orders for chipmakers and equipment suppliers.

Not everyone agrees on the cause. Some analysts argue the election was merely the spark, and the real issue is stretched AI valuations and long-standing doubts about the return on AI spending. Notably, on Wednesday, November 4, the Dow had jumped 1,569 points in a post-election rally; Thursday wiped it out completely.

How did other markets react?

On Friday the sell-off spread to Asia: Japan’s Nikkei 225 fell 6%, Taiwan’s TAIEX nearly 5% and South Korea’s Kospi 6%. According to Finimize, the Nasdaq 100 ended up 15% below its October peak, putting it in correction territory.

What does it mean for everyday investors?

Despite the drop, the main US indices are still up for 2026: as of the November 5 close, the Nasdaq Composite was up 4.6% and the S&P 500 7.4% year to date. The market gave back much of the year’s gains but did not turn negative. If you hold US tech funds, sharp swings in AI stocks are now the norm, and decisions are better based on your own time horizon than on a single day. This article is not investment advice.

FAQ

How much did the Nasdaq fall on November 5, 2026?

The Composite fell 5.52% and the Nasdaq 100 6.36%, or about $2.5 trillion in market value.

Has the US banned data-centre construction?

No. There is no federal ban; investors reacted to expectations of tighter rules and local ballot measures, not to a new law.

Which stocks fell the most?

Chipmakers and companies that build or lease data centres, including AMD, Micron, Nvidia and CoreWeave.

Sources: Reuters / The Express Tribune, Political.org, Finimize, investingLive, AI Unraveled.