Abstract: A copper base alloy having an improved combination of conductivity and strength for applications such as lead frames or electrical connectors. The alloys consists essentially of from about 0.3 to 1.6% by weight iron, with up to one-half the iron content being replaced by nickel, manganese, cobalt, and mixtures thereof; from about 0.01 to about 0.20% by weight magnesium; from about 0.10 to about 0.40% by weight phosphorus; up to about 0.5% by weight tin or antimony and mixtures thereof; and the balance copper. The phosphorus to magnesium ratio and phosphorus to the total content of phosphide formers ratio are maintained within critical limits.