A contact insert for clamping an electric conductor to a clamping point by a clamping spring. The contact insert has a contact frame having at least one contact base and a respective lateral wall arranged at an angle to the contact base, wherein the lateral walls run substantially parallel to each other, and a receiving area is formed between the lateral walls. The clamping spring is arranged in the receiving area. The clamping spring has a contact arm, a spring bend, which adjoins the contact arm, and a clamping arm, which adjoins the spring bend. The contact arm is secured to one or both lateral walls or to at least one securing wall, which adjoins one or both lateral walls. The clamping arm is pretensioned relative to the contact base. The clamping point for the electric conductor to be clamped is formed between the clamping arm and the contact base.