Terminal fitting

A terminal fitting has a resilient contact piece (18) coupled to an inner ceiling wall (15) via a resilient supporting piece (17). The resilient contact piece (18) is cantilevered back from the resilient supporting piece (17) and then is bent forward. A portion of the resilient contact piece (17) is resiliently deformable upward and downward with a folded portion (20) as a center. The resilient contact piece (18) is entirely displaceable along the longitudinal direction with the resilient supporting piece (17) as a center. An auxiliary spring portion (30) has a first and a second curves (32) that project up and down immediately before the folded portion (20) of the resilient contact piece (18). The auxiliary spring portion (30) can be elongated and contracted resiliently along the same direction.