Stock Market Drop 401k Math: What a 5% Fall Costs You

Piggy bank, calculator and coins for retirement savings (stock market drop 401k)

The S&P 500 is down 5.0% over the past month, so most stock-heavy 401k balances are lower too. Yahoo Finance data through November 6, 2026 shows the Nasdaq Composite fell 9.61% over the same month, which means the stock market drop 401k savers are feeling is sharper in plans that lean on growth or tech funds. For most savers with years to go, the dollar loss is smaller than it feels. The bigger risk is what you do ne…