US manufacturing contracted again in September, with the Institute for Supply Management's Purchasing Managers' Index remaining below 50, the threshold separating expansion from contraction. The reading extended a run of nine consecutive monthly declines in factory activity.

The ISM survey, published on the first business day of October, is among the earliest hard indicators of how American producers fared over the previous month. Economists at Goldman Sachs and JPMorgan had forecast a headline figure in the high 48 to low 49 range, reflecting persistent softness in new orders and employment sub-indices.

Manufacturers continued to cite elevated input costs tied to tariffs on imported components and metals, alongside cautious capital spending by customers. The prices-paid component stayed elevated, signalling that cost pressures had not eased even as demand weakened—a combination that squeezed factory margins during the quarter.

The report landed as a federal government shutdown clouded the release of official economic data, raising the profile of private surveys such as ISM. Investors and Federal Reserve officials leaned more heavily on these figures to gauge the economy's trajectory ahead of the central bank's next policy meeting.

Respondents across several industries reported flat or declining order books, according to the Institute for Supply Management. A minority pointed to stabilising demand in aerospace and defence-related segments.