The susceptibility of YbxSc1−xAl3(Cu3Au‐type structure) forx=0.1, 0.2, 0.5 and 1.0 has been measured from 4.2 to 700 K. In contrast to Ce‐Th alloys, the addition of a smaller atom, Sc, to YbAl3favors the configuration with a larger atomic volume, Yb2+. The susceptibility per mole Yb exhibits a broad maximum which shifts to lower temperatures with increasingx. Room temperature lattice constant measurements indicate that the valance increases gradually from ∼2.7 atx=0.1 to ∼2.9 atx=1.0. Fitting our data to the resonant level‐type model of Sales, we find that the width of the resonant level ‐ decreases dramatically with increasingx. All the data approximately satisfies a scaling relationship.