The Energy Information Administration, the statistical arm of the Energy Department, said April exports were the highest since 1999 and continue a trend that began last year.
Crude oil exports are restricted by legislation enacted in response to the Arab oil embargo in the 1970s. EIA said a company needs to get a special license from the Department of Commerce to get around restrictions.
"Almost all of the crude oil exported from the United States has been delivered to Canada, and most of the recent increase in crude oil exports has been from the U.S. Gulf Coast," EIA said.
Gulf Coast exports, from the so-called Petroleum Administration for Defense District 3, averaged 134,000 bpd during the first quarter of 2014. That's a 283 percent increase over last year.
EIA attributed the increase in crude oil exports to rising U.S. crude oil production. In its monthly market report, published Tuesday, EIA said it estimated U.S. oil production in May averaged 8.4 million bpd, the highest monthly average in a quarter century.