Part of the reason for the increase in crude supplies was less demand from refineries, where activity decreased with maintenance season in effect. Refinery utilization fell to 89.8% last week from 90.9%. Read: Gasoline prices stop falling as refinery maintenance season kicks in

The U.S. Energy Information Administration reported Wednesday an increase of four million barrels in crude supplies for the week ended Sept. 25. That was the first climb in three weeks. Analysts polled by Platts expected supplies to be unchanged, while the American Petroleum Institute Tuesday said supplies jumped 4.6 million barrels.

November Brent crude LCOX5, +0.54%  on London’s ICE Futures exchange tacked on 14 cents, or 0.3%, to $48.37 a barrel. Year to date, prices have fallen more than 15%.

November West Texas Intermediate crude CLX5, +0.27%  settled at $45.09 a barrel, down 14 cents, or 0.3%, on the New York Mercantile Exchange, trading between a high of $45.85 and a low of $44.68, according to FactSet data.

Oil futures tallied a loss of 24% for the third quarter, after ending Wednesday lower on the back of a report revealing the first U.S. crude-supply increase in three weeks.