For the third consecutive month, gains beat expectations of economists. The consensus forecast called for a gain of 140,000 jobs.
The June to July reported gain of 163,000 jobs was revised higher to 173,000.
ADP said firms with fewer than 50 employees in July added 99,000 jobs after adding 73,000 in the previous month. Companies with 51 to 499 employees added 86,000 jobs, an improvement over June to July's gain of 67,000 jobs. Firms with more than 500 workers added 16,000 jobs, fewer than the 23,000 jobs at large firms added in the previous month.
ADP said 185,000 of the new jobs were in service-providing businesses, while goods-producing firms added 16,000.
The monthly report anticipates Friday's government report on jobs, which includes private and public sector employment.
Manufacturing employment gained 3,000 jobs after adding 6,000 jobs in July and 9,000 in June.
The construction sector added 10,000 jobs, the third consecutive month of gains.