US milk production continues to grow strongly through September, as herd expansion and higher productivity drive output across major producing states. Idaho, Texas, New York, and California led the gains, while only a handful of states saw modest declines. Yet, this robust growth comes amid falling milk prices and tightening margins, with the average price dropping more than 11% compared to last year. Meanwhile, replacement heifer inventories have fallen to their lowest level in two decades, raising concerns about future herd renewal. The US dairy sector remains productive but increasingly vulnerable to market and structural pressures, potentially affecting the long-term sustainability of production.