The business index for July rose from 12.5 to 19.8, reaching its highest level since March 2011, the Fed said.
In the month, 37 percent of businesses responding to the Fed's monthly survey indicated business was increasing, while 17 percent indicated business was contracting.
The Fed said the new orders index slid six points to 10.2, but remained positive. The shipments index, meanwhile, rose "notably," the Fed said, climbing from 4.1 in June to 14.3.
Respondents indicated a draw down in inventories with the index for stocked items dropping 15 points from minus 6.6 to minus 21.6.
In the survey taken the first two weeks in July, 18 percent of businesses indicated they were hiring, while 10 percent indicated their payrolls were shrinking.
The index measuring number of hours at work also rose, the Fed said.