The U.S. refines a mix, but its refineries are built for heavier, sourer crude, so the U.S. actually imports significant amounts of heavy crude (like from Canada) to blend with its predominantly light, sweet crude domestic production, as most U.S. refineries need that heavier oil for efficient operation and to produce specific products like asphalt and heavy fuel oils.
U.S. Production is Light & Sweet: The majority of oil produced in the United States (from shale, etc.) is light (thinner) and sweet (low sulfur).
Refineries Need Heavy Crude: U.S. refineries, with significant investments made decades ago, are optimized to process heavier, sourer (higher sulfur) crude.
Imports Fill the Gap: To run efficiently and produce all necessary products (gasoline, diesel, asphalt, etc.), the U.S. imports heavy crude, primarily from Canada, Mexico, and Colombia.
The Mix: Refineries use a blend of domestic light crude and imported heavy crude to maximize output and run efficiently.
The U.S. imports crude oil from Venezuela, primarily heavy sour crude processed by Gulf Coast refineries, with imports fluctuating due to sanctions and licensing but continuing under specific carve-outs, notably for Chevron's operations. While U.S. imports dropped significantly after 2019 sanctions, exemptions have allowed a resumption, making Venezuela a key supplier for specialized U.S. refineries, even as the overall volume remains a fraction of historical highs.