Saudi Aramco's oil output capacity reached 12m barrels a day in June when three new projects were brought on stream.
One of those projects was the 250,000 barrels per day Shaybah oilfield expansion, company boss Khalid al-Falih told the al-Hayat newspaper.
The project is the last of an expansion plan to boost the country's total capacity to 12.5m bpd.
The capacity of the world's top oil exporter is about 500,000bpd higher than Aramco's, as the shared Neutral Zone with Kuwait is not counted in the state company's capacity, wrote Reuters.
Saudi Aramco's production capacity was 12m bpd in June, when output started from three fields: Nuayyim, Khurais and Shaybah, Falih told the newspaper.
He went on to say that the kingdom had expected to produce more than 10m bpd of oil by the time it completed its crude capacity expansion plan, which would be nearly 2m bpd higher than current output. According to a Reuters survey this would be at about 8m bpd in June.
However, the economic slowdown has cut crude demand, leading Opec to reduce output to match sliding consumption. Opec pledged to cut output by 4.2m bpd last year, about 5% of global supply.
Saudi Arabia, which is Opec's largest producer, shouldered most of the cuts, reducing output by more than 1.5m bpd from about 9.54m bpd in August, according to Reuters.
The result is a spare capacity of about 4.5m bpd, more than double the 1.5m-2m bpd extra supply it has a policy of keeping to meet any unexpected disruption in global supply.