In its monthly report compiled with Macroeconomic Advisors, ADP said the service sector accounted for the bulk of the creation, with 270,000 jobs while goods producers supplied the remaining 27,000.

Manufacturing saw a gain of 23,000 jobs while construction was unchanged. Large businesses saw the fewest gains, with 36,000 jobs, while medium-sized businesses, with between 50 and 499 workers, created 144,000 positions.

The number was far higher than the 100,000 economists expected the ADP report to show and sets the stage for what could be a positive surprise Friday when the government releases its monthly nonfarm jobs report. That report is expected to show 140,000 jobs were created.

Economists sometimes will use the ADP report to fine-tune their numbers, though the report has varied in its ability to predict the true national jobless picture.

"In the underlying ADP data there is a very clear pattern of acceleration now," Joel Prakken, chairman of Macroeconomic Advisors, told CNBC shortly after the report was released. "I would not discount today's number as a total fluke. I think there is a strong signal in here."