The left hepatic duct and the right hepatic duct transfer bile from the liver. These ducts are formed by the intrahepatic ducts and are a part of a ductal system that leads to the gallbladder.

These ducts exit the liver in a common sheath, alongside the branches of the hepatic artery and portal vein. The bile that flows through the right and left hepatic ducts drains into the common hepatic duct.

The size of the left hepatic duct depends on the quadrate lobe’s width. It is located behind the portal vein’s left branch.

The left hepatic duct enters the upper end of the liver’s umbilical fissure — a groove in the liver that separates the right and left lobes — where it is joined by other duct tributaries that extend to segments II, III, and IV of the liver.

Sixty percent of the time, the left hepatic duct unites with the right hepatic duct outside of the liver. The other forty percent of the time, the right posterior and anterior ducts enter the left hepatic duct separately.