A shaving razor cartridge (12, 1012) comprising: a housing that extends between a front end and a rear end, the housing comprising: a blade support portion positioned between the front end and the rear end and comprising: a cap; and a guard spaced from the cap and cooperating with the cap to define a shaving plane; and a handle interface portion positioned between the front end and the rear end and comprising: a front wall comprising a lower surface and an interior surface, the interior surface extending along a front plane; a rear wall (48, 1048) comprising a lower surface and an interior surface, the interior surface extending along a rear plane; an upper surface; and a front lip portion disposed between the front wall and the upper surface and comprising an interior surface; and at least one razor blade disposed in the blade support portion between the cap and the guard, wherein: the lower surfaces (58, 60) cooperate to define a lower opening (64, 1064); the front wall and the front lip portion are each spaced from the rear wall (48, 1048) such that the interior surfaces (52, 54, 76) of each of the front wall, the rear wall (48, 1048), and the front lip portion cooperate to at least partially define a handle receptacle that extends to the lower opening (64, 1064); the rear wall (48, 1048) is more proximate to the blade support portion than the front wall; the interior surface of the front wall and the interior surface of the front lip portion are non-coplanar; and the front lip portion is configured to engage a portion of a handle. a housing that extends between a front end and a rear end, the housing comprising: a blade support portion positioned between the front end and the rear end and comprising: a cap; and a guard spaced from the cap and cooperating with the cap to define a shaving plane; and a handle interface portion positioned between the front end and the rear end and comprising: a front wall comprising a lower surface and an interior surface, the interior surface extending along a front plane; a rear wall (48, 1048) comprising a lower surface and an interior surface, the interior surface extending along a rear plane; an upper surface; and a front lip portion disposed between the front wall and the upper surface and comprising an interior surface; and at least one razor blade disposed in the blade support portion between the cap and the guard, wherein: the lower surfaces (58, 60) cooperate to define a lower opening (64, 1064); the front wall and the front lip portion are each spaced from the rear wall (48, 1048) such that the interior surfaces (52, 54, 76) of each of the front wall, the rear wall (48, 1048), and the front lip portion cooperate to at least partially define a handle receptacle that extends to the lower opening (64, 1064); the rear wall (48, 1048) is more proximate to the blade support portion than the front wall; the interior surface of the front wall and the interior surface of the front lip portion are non-coplanar; and the front lip portion is configured to engage a portion of a handle. a blade support portion positioned between the front end and the rear end and comprising: a cap; and a guard spaced from the cap and cooperating with the cap to define a shaving plane; and a cap; and a guard spaced from the cap and cooperating with the cap to define a shaving plane; and a handle interface portion positioned between the front end and the rear end and comprising: a front wall comprising a lower surface and an interior surface, the interior surface extending along a front plane; a rear wall (48, 1048) comprising a lower surface and an interior surface, the interior surface extending along a rear plane; an upper surface; and a front lip portion disposed between the front wall and the upper surface and comprising an interior surface; and a front wall comprising a lower surface and an interior surface, the interior surface extending along a front plane; a rear wall (48, 1048) comprising a lower surface and an interior surface, the interior surface extending along a rear plane; an upper surface; and a front lip portion disposed between the front wall and the upper surface and comprising an interior surface; and at least one razor blade disposed in the blade support portion between the cap and the guard, wherein: the lower surfaces (58, 60) cooperate to define a lower opening (64, 1064); the front wall and the front lip portion are each spaced from the rear wall (48, 1048) such that the interior surfaces (52, 54, 76) of each of the front wall, the rear wall (48, 1048), and the front lip portion cooperate to at least partially define a handle receptacle that extends to the lower opening (64, 1064); the rear wall (48, 1048) is more proximate to the blade support portion than the front wall; the interior surface of the front wall and the interior surface of the front lip portion are non-coplanar; and the front lip portion is configured to engage a portion of a handle. the lower surfaces (58, 60) cooperate to define a lower opening (64, 1064); the front wall and the front lip portion are each spaced from the rear wall (48, 1048) such that the interior surfaces (52, 54, 76) of each of the front wall, the rear wall (48, 1048), and the front lip portion cooperate to at least partially define a handle receptacle that extends to the lower opening (64, 1064); the rear wall (48, 1048) is more proximate to the blade support portion than the front wall; the interior surface of the front wall and the interior surface of the front lip portion are non-coplanar; and the front lip portion is configured to engage a portion of a handle.