Orders dropped further than expected as economists had predicted a slide of 4.4 percent.
Orders retreated to $217 billion, off $11.8 billion from December, which had posted the category's fourth consecutive month of increases.
Transportation orders, down for three of the past four months, "drove the decrease," by dropping 19.8 percent ($14.7 billion) from December to $59.7 billion.
Within that segment, defense aircraft orders fell the furthest, dropping $5.1 billion in the month, the report said.
Shipments of durable goods, which are goods expected to last at least three years, dropped by 1.2 percent month to month to $226.1 billion -- a slide that follows a 0.5 percent increase on the previous month.
Inventories rose by 0.2 percent to $374.8 billion, climbing for the 15th month out of the last 16.
Non-defense capital goods orders, a leading economic index, dropped 0.1 percent -- $100 million -- to $72.22 billion.
Capital goods orders represent manufacturing firms investing in themselves by purchasing production equipment. It is viewed as a sign that manufacturers believe production warrants further investment.