Following a gain of 185,000 jobs in December, ADP said firms with under 50 employees added 115,000 jobs in January, while medium sized firms added 79,000.
Firms with 500 to 999 employees added 7,000 jobs in January, but firms with 1,000 employees or more lost 9,000 positions, ADP said.
Economists expected 165,000 jobs were added in January. ADP, meanwhile, lowered its December estimate of jobs gained from 215,000 to 185,000.
ADP said the construction sector added 15,000 jobs in the month. Manufacturing firms gave up 3,000. Trade, transportation and utilities as a group added 33,000 jobs, financial services another 12,000 and professional business services an additional 40,000.
In a separate breakdown, goods producing jobs rose by 15,000, most of that coming from the construction industry. Service oriented jobs increased by 177,000.
According to the ADP's figures, the economy has added an average of 183,000 jobs per month during the last three months. "This is an encouraging sign of steady improvement in the job market," said ADP President and Chief Executive Officer Carlos Rodriguez in a statement.