Costco Stock (COST) After Hours Today (Dec. 18, 2025): Price Action, Fresh Forecasts, and What to Watch Before Friday’s Market Open
Costco Wholesale Corporation (NASDAQ: COST) finished Thursday’s regular session under modest pressure—and then barely budged after the closing bell, a sign that traders are still digesting the same debate that has dominated Costco’s tape for much of 2025: strong operating performance vs. a still-premium valuation. By the 4:00 p.m. ET close on December 18, 2025, COST ended at $857.59, down…