This fluid coupling (R) element (200) comprises a body (202) for receiving a complementary end-piece (100), this body being centered on a longitudinal axis (X2) and defining a fluid circulation channel (204) within the body on the one hand, and a sealing chamber (208) in which a sealing gasket able to cooperate with the end-piece (100) inserted in the body (202) is housed, on the other hand. The sealing chamber is defined by an outer radial wall (2082) and a rear wall (2088). This coupling element comprises a locking mechanism (206) that includes locking members (2062) radially movable in the body relative to the longitudinal axis (X2), between a position blocking the end-piece (100) in the body and a position freeing a passage for the end-piece, and a locking ring (2066) mounted around the body and movable relative thereto, between a first position keeping the locking members (2062) in their blocking position and a second position in which the locking ring does not oppose the movement of the locking members toward their released position. The sealing chamber (208) is inwardly radially defined, relative to the longitudinal axis (X2), by an inner radial wall (2084), secured to the body (202), and by a front wall (2086). A front edge (2084b) of the inner radial wall (2084) is offset backward (d1), along the longitudinal axis (X2), relative to the rear surface (2086s) of the front wall (2086).