The Pacific razor clam, Siliqua patula, is a species of large marine bivalve mollusc in the family Pharidae.
This species has an elongated oblong narrow shell, which ranges from 8 to 15 cm (3 to 6 in) in length in the southern portion of its range, with individuals up to 28 cm (11 in) found in Alaska. It is similar to the smaller Atlantic razor clam, Siliqua costata, which is found on the East Coast of the United States.
The name razor clam is also used for the Atlantic jackknife clam, Ensis directus. The Atlantic jackknife clam's genus, Ensis, is different than the Pacific razor clam's genus, Siliqua. However, they are both in the same family, Pharidae.
Pacific razor clams can be found along the Pacific West Coast of North America from the eastern Aleutian Islands, Alaska, to Pismo Beach, California. They inhabit sandy beaches in the intertidal zone down to a maximum water depth of about 9 m (30 ft).